focus

American  

[foh-kuhs] / ˈfoʊ kəs /

noun

• focuses,
  plural
• focusses,
  plural (especially British)
• foci
  plural (especially British)

1. a central point, as of attraction, attention, or activity.

   The need to prevent a nuclear war became the focus of all diplomatic efforts.

   Synonyms:

   nucleus, core, heart, center

2. close attention or concentration.

   Some of the warning signs indicating you should pull over: drifting between lanes, repeated yawning, tailgating, and trouble maintaining focus.

3. the ability to concentrate one’s attention or to sustain concentration.

   Mindfulness and meditation are often suggested to help manage stress, increase awareness of emotions, and improve focus.

4. Physics. a point at which rays of light, heat, or other radiation meet after being refracted or reflected.

5. Optics.

   1. the focal point of a lens, on which rays converge or from which they deviate.

   2. the focal length of a lens; the distance from a focal point to a corresponding principal plane.

   3. the clear and sharply defined condition of an image.

   4. the position of a viewed object or the adjustment of an optical device necessary to produce a clear image.

      in focus; out of focus.

6. Geometry. (of a conic section) a point having the property that the distances from any point on a curve to it and to a fixed line have a constant ratio for all points on the curve.

7. Geology. the point of origin of an earthquake.

8. Pathology. the primary center from which a disease develops or in which it localizes.

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verb (used with object)

• focuses,
  present (3rd person singular)
• focused,
  past participle,  past
• focussed,
  past participle,  past (especially British)
• focusing,
  present participle
• focussing
  present participle (especially British)

1. to bring to a focus or into focus; cause to converge on a perceived point.

   to focus the lens of a camera.

2. to concentrate.

   to focus one's thoughts;

   to focus troop deployment in the east.

verb (used without object)

• focuses,
  present (3rd person singular)
• focused,
  past participle,  past
• focussed,
  past participle,  past (especially British)
• focusing,
  present participle
• focussing
  present participle (especially British)

1. to be or become focused.

   My eyes have trouble focusing on distant objects.

2. to direct one's attention or efforts.

   Students must focus in class.

focus British  

/ ˈfəʊkəs /

noun

1. a point of convergence of light or other electromagnetic radiation, particles, sound waves, etc, or a point from which they appear to diverge

2. another name for focal point focal length

3. optics the state of an optical image when it is distinct and clearly defined or the state of an instrument producing this image

   the picture is in focus

   the telescope is out of focus

4. a point upon which attention, activity, etc, is directed or concentrated

5. geometry a fixed reference point on the concave side of a conic section, used when defining its eccentricity

6. the point beneath the earth's surface at which an earthquake or underground nuclear explosion originates Compare epicentre

7. pathol the main site of an infection or a localized region of diseased tissue

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verb

1. to bring or come to a focus or into focus

2. to fix attention (on); concentrate

focus Scientific  

/ fō′kəs /

1. The degree of clarity with which an eye or optical instrument produces an image.

2. See focal point

3. A central point or region, such as the point at which an earthquake starts.

4. Mathematics A fixed point or one of a pair of fixed points used in generating a curve such as an ellipse, parabola, or hyperbola.

5. The region of a localized bodily infection or disease.

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Usage

Where does focus come from? What does the word focus bring to your mind? Maybe you think of a photograph that is clear and sharply defined. Or perhaps you recall a teacher tsk-tsking you to pay attention in class. But what about a fireplace?Well, the word focus comes directly from the Latin focus, which meant “fireplace” or “hearth” (that is, the floor of a fireplace). This is what focus originally meant in English when the word entered the language around 1635–45, though that sense has been extinguished, as it were. But the word focus burned on in other ways. As the 1600s unfolded, focus was given new meanings in the great scientific literature of that age, which were largely written in what’s known as New Latin. In the 1650s, the influential English philosopher and author Thomas Hobbes used focus for a kind of fixed point in geometry. So did Isaac Newton—you know, of gravity fame—in the 1690s. Other applications of the word focus in the late 1600s came about in the fields of medicine and physics. In physics, a focus is “a point at which rays of light, heat, or other radiation meet after being refracted or reflected.” Perhaps you can imagine how a fireplace or a hearth—contained areas and sources of heat and light—was likened to such a point in math and science. Dig deeperThe word focus took on a number of senses in optics, specifically “the point on a lens on which rays converge or from which they deviate.” A more familiar sense of focus is “the clear and sharply defined condition of an image,” as when the image isn’t blurry. Optics has also given us the expressions in focus and out of focus, which can be used both literally and figuratively. From these various ideas of clarity and convergence in optics arises one of the more common, everyday ways we use the word focus today: “a central point, as a of attention, activity, or activity.” For example, Finding a cure for cancer was the focus of his long career. Focus also refers to ability to concentrate, as in The teacher felt the students struggled with their focus. These senses of focus had spread by the early 1800s, around when various verb forms of focus take off. The adjective form of focus is focal.

Other Word Forms

Derived Forms

• focuser
  noun
• misfocus
  verb
• refocus
  verb
• overfocus
  verb (used with object)
• focusable
  adjective
• misfocused
  adjective
• misfocussed
  adjective
• self-focused
  adjective
• self-focusing
  adjective
• unfocusing
  adjective
• well-focused
  adjective

Inflected Forms

Nouns

• foci
  plural
• focuses
  plural
• focusses
  plural

Participles

• focusing
  present
• focussing
  present
• focused
  past
• focussed
  past

Conjugated Forms

Present

• focus
  simple
• focuses
  simple
• have focused
  perfect
• have focussed
  perfect
• has focused
  perfect
• has focussed
  perfect
• am focusing
  progressive
• am focussing
  progressive
• are focusing
  progressive
• are focussing
  progressive
• is focusing
  progressive
• is focussing
  progressive
• have been focusing
  perfect progressive
• have been focussing
  perfect progressive
• has been focusing
  perfect progressive
• has been focussing
  perfect progressive

Past

• focused
  simple
• focussed
  simple
• had focused
  perfect
• had focussed
  perfect
• was focusing
  progressive
• was focussing
  progressive
• were focusing
  progressive
• were focussing
  progressive
• had been focusing
  perfect progressive
• had been focussing
  perfect progressive

Future

• will focus
  simple
• will have focused
  perfect
• will have focussed
  perfect
• will be focusing
  progressive
• will be focussing
  progressive
• will have been focusing
  perfect progressive
• will have been focussing
  perfect progressive

Etymology

Origin of focus

First recorded in 1635–45; Latin: “fireplace, hearth”

Explanation

Focus is something that camera lenses and sleepy students are always being asked to do. For cameras, it means finding a point where the subject is clear or "in focus." For students, it means paying attention. Focus is all about finding a center — of a parabolic curve, of a lens, of a meditative state. In Latin, focus meant 'domestic hearth,' which just goes to show that not much has changed — since kitchens remain the focus of the modern home. Focus can be used as a verb, as in "I need to focus on my work, so I can play video games later;" and as a noun, as in "What is the focus of this essay? I can't tell, since the writer seems to be all over the place."

Example Sentences

See Examples For:

focus foci focuses focusses focused focussed focusing focussing

If an aircraft crashes, we focus on finding the engineering defect, correcting it, and enforcing established liability standards for the damage created.

From The Wall Street Journal ● Sep. 21, 2026

But the focus of this book is much more about the Diana era - and an elegy to the lost world of their childhood.

From BBC ● Sep. 21, 2026

China will be in focus this week as the country’s president, Xi Jinping, travels to Washington for a summit with U.S.

From MarketWatch ● Sep. 21, 2026

Their focus was on tidal disruption events, which occur when a star passes so close to a supermassive black hole that intense gravitational forces rip it apart.

From Science Daily ● Sep. 21, 2026

“My focus is the property seizure,” Dad says.

From "South of Somewhere" by Kalena Miller

The fasting mice had better blood values, less fatty liver and liver inflammation and above all: they developed less liver cancer and had fewer cancer foci in the liver.

From Science Daily ● May 7, 2024

One of the foci will be located at the origin.

From Textbooks ● Dec. 21, 2021

TRY IT #7 Graph the ellipse given by the equation Identify and label the center, vertices, co-vertices, and foci.

From Textbooks ● Sep. 23, 2020

A line drawn through the foci intersect the ellipse in two points.

From Textbooks ● May 6, 2020

Ellipses have two centers, or foci; the more elongated the ellipse, the farther apart these foci are.

From "Zero: The Biography of a Dangerous Idea" by Charles Seife

Trained as a forensic pathologist, Ms. Margolles focuses on violence and the forces that drive it in sculptures, photographs and more.

From The Wall Street Journal ● Sep. 20, 2026

Together with Ross and producer Steven Schneider he launched a company called Spooky Pictures that focuses on low-budget horror.

From The Wall Street Journal ● Sep. 20, 2026

The company has been pivoting to a broader platform and strategy — a “relationship-based selling” approach, whereby it focuses on catering to existing customers and selling them new products.

From MarketWatch ● Sep. 17, 2026

New research published in Science Translational Medicine focuses on primary aldosteronism, a hormone disorder that may affect up to one in five people with high blood pressure.

From Science Daily ● Sep. 14, 2026

When my camera lens focuses on that tiny pale white dot, I feel so far away from them.

From "A Rover's Story" by Jasmine Warga

"The metallic tip acts like an antenna and focusses the electromagnetic field in a tiny area below its apex."

From Science Daily ● Nov. 20, 2024

“This shocking news focusses our minds on Michael’s wife Clare and their sons,” said Roy Taylor, a professor of medicine and metabolism at Newcastle University who co-authored “The 8-Week Blood Sugar Diet” with Mosley.

From Seattle Times ● Jun. 7, 2024

The unemployment rate has fallen from 8.5% in 2011 to 3.8% in 2023, said the think tank, which focusses on improving the living standards for those on low to middle incomes.

From BBC ● Apr. 14, 2024

This latest research focusses on how this happens at the structural level.

From Science Daily ● Dec. 5, 2023

Yet the head analogy is useful, since it focusses our attention to these various subtleties.

From Definition & Reality in the General Theory of Political Economy by Thomas Colignatus

She has mostly stuck to promoting her decades-long record on the campaign trail, which has recently focused on increased healthcare access for seniors, workforce development and Social Security benefit increases.

From Los Angeles Times ● Sep. 21, 2026

Private-equity firms Shamrock Capital and Flexpoint Ford have acquired Podium Entertainment, a book publisher focused on independent authors and audiobooks, for north of $400 million, according to people familiar with the matter.

From The Wall Street Journal ● Sep. 21, 2026

While equity investors are focused on the soaring demand for chips and servers, the credit markets are beginning to price in the structural fragility of the AI trade, according to Haissl.

From MarketWatch ● Sep. 21, 2026

The first series focused on Mary, the couple's seemingly unremarkable middle daughter as she navigates the societal pressures of Regency England.

From BBC ● Sep. 21, 2026

At the moment, there were seven other Elders focused on prep work—dicing vegetables for stew, carving meat off carcasses.

From "Legendary Frybread Drive-In" by Cynthia Leitich Smith

Across Caracas and La Guaira, many were focussed instead on Sunday services in churches to remember those lost and still missing.

From Barron's ● Jul. 5, 2026

Downing Street declined to comment on the essay before it was published, but said Sir Keir was "fully focussed on delivering change for working people".

From BBC ● May 26, 2026

A number of other parties focussed on picking up seats this way, which sees MSPs elected in wider electoral regions.

From BBC ● May 10, 2026

In the meantime, Zelensky has focussed on bolstering Ukraine where he can.

From BBC ● May 2, 2026

“Partly on his interest being focussed on what he calls ‘the soul,’ which he persists in regarding as an entity independent of the physical environment, whereas, as I tried to point out to him ...”

From "Brave New World" by Aldous Huxley

Sullivan has argued that medical countermeasures should be developed more broadly for pathogens capable of causing severe illness or death in humans, rather than focusing only on viruses already known to cause frequent outbreaks.

From Science Daily ● Sep. 20, 2026

While brand partnerships can be hard to precisely value, Coplan seemed uninterested in analyzing whether the deals would pay off, said a person involved with the deals, focusing instead on locking up partnerships.

From The Wall Street Journal ● Sep. 20, 2026

The company, which originally focused on photonics for industrial applications and eventually moved into telecommunications, is now focusing on AI.

From MarketWatch ● Sep. 19, 2026

Prince William and the Princess of Wales were on the Isle of Bute on Thursday focusing on royal duty rather than family fallout.

From BBC ● Sep. 18, 2026

Zohra’s eyes are darting around the room instead of focusing on me.

From "Amina's Song" by Hena Khan

It has been promoted as a means of bringing people together in the shared story of their traumatic past, with "reparations" quite literally focussing on "repair" at a very human level.

From BBC ● Aug. 16, 2026

The NHS was thought to have only two weeks' supply in stock and so was focussing on emergency patients and the most complex cases on the waiting list.

From BBC ● Feb. 24, 2026

Dr Becks Fisher said, of the Nuffield Trust think tank, said the service will be helpful for some and focussing on menopause and menstrual health "makes sense" given the long waits for gynaecology services.

From BBC ● Jan. 5, 2026

He says rather than focussing on extending life-span, we should instead strive for healthy years lived.

From BBC ● Sep. 4, 2025

Occasionally, focussing on a linguistic alteration can mislead us into thinking that something important has happened when it hasn’t, or that something happened at a particular moment when it actually happened earlier.

From "The Invention of Science" by David Wootton

Related Words

• apply oneself to
• concentrate
• engage
• fixate
• pay attention to
• pore over