capsule

American  

[kap-suhl, -sool, -syool] / ˈkæp səl, -sul, -sjul /

noun

capsules plural

1. Pharmacology. a gelatinous case enclosing a dose of medicine.

2. Biology.

   1. a membranous sac or integument.

   2. either of two strata of white matter in the cerebrum.

   3. the sporangium of various spore-producing organisms, such as ferns, mosses, algae, and fungi.

3. Botany. a dry dehiscent fruit, composed of two or more carpels.

4. a small case, envelope, or covering.

5. Also called space capsule.  Aerospace. a sealed cabin, container, or vehicle in which a person or animal can ride in flight in space or at very high altitudes within the earth's atmosphere.

6. Aviation. a similar cabin in a military aircraft, which can be ejected from the aircraft in an emergency.

7. a thin metal covering for the mouth of a corked bottle.

8. a concise report; brief outline.

   An appendix to the book contains biographical capsules of the contributors.

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verb (used with object)

capsuled, capsuling

1. to furnish with or enclose in or as if in a capsule; encapsulate.

2. to capsulize.

adjective

1. small and compact.

2. short and concise; brief and summarized.

   a capsule report.

3. containing only the most essential and versatile items of a particular kind.

   capsule wardrobe;

   capsule pantry.

capsule British  

/ ˈkæpsjuːl /

noun

1. a soluble case of gelatine enclosing a dose of medicine

2. a thin metal cap, seal, or cover, such as the foil covering the cork of a wine bottle

3. botany

   1. a dry fruit that liberates its seeds by splitting, as in the violet, or through pores, as in the poppy

   2. the spore-producing organ of mosses and liverworts

4. bacteriol a gelatinous layer of polysaccharide or protein surrounding the cell wall of some bacteria: thought to be responsible for the virulence in pathogens

5. anatomy

   1. a cartilaginous, fibrous, or membranous envelope surrounding any of certain organs or parts

   2. a broad band of white fibres ( internal capsule ) near the thalamus in each cerebral hemisphere

6. See space capsule

7. an aeroplane cockpit that can be ejected in a flight emergency, complete with crew, instruments, etc

8. (modifier) in a highly concise form

   a capsule summary

9. (modifier) (in the fashion industry) consisting of a few important representative items

   a capsule collection

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capsule Scientific  

/ kăp′səl,-so̅o̅l /

1. A dry dehiscent fruit that develops from two or more carpels, as in the poppy and the cottonwood tree.

2. The sporangium (the hollow spore-producing structure) of mosses and other bryophytes.

3. The outer layer of viscous polysaccharide or polypeptide slime with which some bacteria cover their cell walls. Capsules provide defense against phagocytes and prevent the bacteria from drying out.

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Other Word Forms

Derived Forms

• uncapsuled
  adjective

Inflected Forms

Nouns

• capsules
  plural

Etymology

Origin of capsule

First recorded in 1645–55; 1950–55 capsule for def. 5; from French or directly from Latin capsula, equivalent to caps(a) “box” + -ula diminutive suffix; see origin at case ², -ule

Explanation

A capsule is a very small container that closes tightly. Many medicines come in capsules that can be easily swallowed. Certain brands of laundry or dishwasher soap can be bought in capsule form, and you might hide a secret note or special mementos in a time capsule. A biologist probably thinks of a capsule as an anatomical structure that encloses an organ. This, in fact, is the word's earliest meaning — in French, it's a "membranous sac," from the Latin capsula, "small box or chest."

Example Sentences

See Examples For:

capsule capsules capsuled capsuling

Among that group, the peripatetic Roger Brown is the subject of a capsule show at GRAY’s New York outpost.

From The Wall Street Journal ● Jul. 24, 2026

Sunfish have a gelatinous outer layer known as capsule, and both this layer and the skin contain a distinct microbiome.

From Science Daily ● Jul. 23, 2026

The contents of the Washington one are not widely known but the capsule due to be buried in Philadelphia near Independence Hall has spilled all its secrets.

From Barron's ● Jul. 2, 2026

The branding has worked wonders for the studio’s reputation, leading diehard loyalists to conflate the production-and-distribution company with the art it finances — resulting in capsule collections of merch flying off the digital shelves.

From Salon ● Jun. 23, 2026

He pocketed the capsule and raised an eyebrow at me.

From "The Secret History" by Donna Tartt

Complete coverage of The Times’ All-Star baseball and softball teams, from the players and coaches of the year to capsules on each player and the final 2026 rankings.

From Los Angeles Times ● Jun. 7, 2026

Products passing through the giant site range from insulin capsules and lifestyle drugs to medicated sunblock and drums of sulphuric acid.

From Barron's ● Apr. 5, 2026

And while the Apollo capsules had room for three astronauts, the Orion craft carries four, as equipment was made to be more compact without a loss of functionality.

From Barron's ● Apr. 4, 2026

From beauty lovers to masculinity influencers, everyone is boasting about their “stacks”—the numerous capsules, powders and injections they take regularly in the hopes of achieving a cumulative, self-optimizing effect.

From The Wall Street Journal ● Mar. 18, 2026

“No, I mean—why weren’t you the first test? Why didn’t you try your IK capsules yourself?”

From "The Smartest Kid in the Universe" by Chris Grabenstein

The professional verdict on Belli's conduct of the defense was neatly capsuled in a Texas lawyer's quip: "They found Melvin Belli guilty and gave Jack Ruby the chair."

From Time Magazine Archive

Few Englishmen would think of scrutinizing them, but scrutinized they turn out to be almost a capsuled paraphrase of the Silver Jubilee reign.

From Time Magazine Archive

In a prompt countermove, Ford this week distributed to 150,000 employes copies of the Founder's familiar anti-union views, capsuled under the heading "Fordisms."

From Time Magazine Archive

The reasons why are neatly capsuled in Shirley's cinefantasy with Mitchum, described as "one of those Hollywood movies all about love and what'11-she-wear-next?"

From Time Magazine Archive

Indeed, the history of the U.S. can plausibly be capsuled in a litany of slogans: No taxation without representation.

From Time Magazine Archive

Freedom," he said, capsuling his own political philosophy, "has been defined as the opportunity for selfdiscipline.

From Time Magazine Archive

Related Words

• dose
• pellet
• pill