microscope

American  

[mahy-kruh-skohp] / ˈmaɪ krəˌskoʊp /

noun

1. an optical instrument having a magnifying lens or a combination of lenses for inspecting objects too small to be seen or too small to be seen distinctly and in detail by the unaided eye.

2. Astronomy. Microscope, the constellation Microscopium.

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microscope British  

/ ˈmaɪkrəˌskəʊp /

noun

1. an optical instrument that uses a lens or combination of lenses to produce a magnified image of a small, close object. Modern optical microscopes have magnifications of about 1500 to 2000 See also simple microscope compound microscope ultramicroscope

2. any instrument, such as the electron microscope, for producing a magnified visual image of a small object

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microscope Scientific  

/ mī′krə-skōp′ /

1. Any of various instruments used to magnify small objects that are difficult or impossible to observe the naked eye.

2. ◆ Optical microscopes use light reflected from or passed through the sample being observed to form a magnified image of the object, refracting the light with an arrangement of lenses and mirrors similar to those found in telescopes.

3. See also atomic force microscope electron microscope field ion microscope

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microscope Cultural  

1. A device that produces a magnified image of objects too small to be seen with the naked eye. Such objects are thus called “microscopic.” The microscope is widely used in medicine and biology. Common microscopes use lenses; others, such as electron microscopes, scan an object with electrons, x-rays, and other radiation besides ordinary visible light.

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Etymology

Origin of microscope

First recorded in 1650–60; from New Latin mīcroscopium; micro-, -scope

Explanation

A microscope is a mechanical instrument that magnifies the image of small objects. You would use a microscope to look at something tiny, like an amoeba. First used in the 1650s, microscope is descended from the Modern Latin microscopium, meaning "an instrument for viewing what is small." In science, microscopes are essential for examining material that can't be seen with the naked eye, like bacteria and viruses. In the same vein, you might feel like you're "under a microscope" if you're being very closely observed and scrutinized, like a star in the limelight or a politician in front of the media.

Example Sentences

From reserving a tee time to fending off turf disease, artificial intelligence is putting the game under an algorithmic microscope.

From The Wall Street Journal • Apr. 10, 2026

As a classic unfolded, the game held contrasting fortunes for those Tuchel had under his microscope.

From BBC • Apr. 7, 2026

Lerosey-Aubril spent more than 50 hours working under a microscope with a fine needle to expose its features.

From Science Daily • Apr. 3, 2026

For example, in an offering known as live blood analysis, Gassan examines a patient’s cells under a microscope, looking for patterns within them.

From Slate • Mar. 30, 2026

Then he placed the case on a flat rock and balanced the microscope on top of it.

From "The Evolution of Calpurnia Tate" by Jacqueline Kelly