a small container
"The nurse placed the medication into a small, clear capsule before handing it to the patient."
a pill in the form of a small rounded gelatinous container with medicine inside
"She swallowed the capsule to treat her stomach pain."
a dry dehiscent seed vessel or the spore-containing structure of e.g. mosses
"The botanist examined the capsule under a microscope to identify the tiny spores inside its dry, split-open casing."
a shortened version of a written work
"The magazine published a capsule review of the new novel to save space in its limited layout."
a structure that encloses a body part
"The rib cage acts as a protective capsule enclosing the heart and lungs."
a spacecraft designed to transport people and support human life in outer space
"The crew boarded the capsule before launching into orbit."
a pilot's seat in an airplane that can be forcibly ejected in the case of an emergency; then the pilot descends by parachute
"The pilot escaped the crash when his capsule was jettisoned and he safely descended to the ground using his parachute."
A membranous envelope.
"The pollen grain is enclosed in a tough, protective capsule that shields it during dispersal."
put in a short or concise form; reduce in volume
"capsulize the news"
To form (medicine, etc.) into capsules.
"The pharmacist carefully measured and mixed the ingredients before she could capsule them for distribution."
In plain English: To capsule something means to put it inside a small, sealed container so that nothing can get out.
"He tried to capsule his story into just three sentences, but he kept adding more details instead."
The word entered English from the French capsule, which originally came from the Latin capsula. This Latin term was a diminutive form of capsa, meaning "box.