Capsule vs Case

When to use each in English, with meaning, register, and examples.

Capsule

Top 5,000 (fairly common)C1noun

Case

Top 1,000 (very common)A2noun
Most common: Case
 CapsuleCase
Pronunciation🇬🇧 //ˈkæpsjuːl//🇺🇸 //ˈkæpsəl//🇬🇧 /["/keɪs/"]/🇺🇸 /["/keɪs/"]/
MeaningA small container for medicine or other items.A situation or example.
ExampleShe took a capsule with water to relieve her headache.Please put the documents in the case for safekeeping.
RegisterNeutralNeutral
How commonTop 5,000 (fairly common)Top 1,000 (very common)
CEFR levelC1A2
Part of speechnounnoun
Collocationstime capsule, medication capsule, space capsule, gelatin capsule, dry capsuleclassic, textbook, typical, illustrate, show, cite, arise, occur, study, example, in somebody’s/​this case, case of, case by case, a case in point, be, remain, overstate, classic, textbook, typical, illustrate, show, cite, arise, occur, study, example, in somebody’s/​this case, case of, case by case, a case in point, notorious, tragic, assault, handle, investigate, work on, file, report, officer, on the case, case of, court, criminal, civil, bring, prosecute, pursue, come before somebody, come to court, go to court, in a/​the case, case against, case of, a case to answer, no case to answer, the circumstances of a case, compelling, convincing, good, have, prepare, outline, exist, case against, case for, the case for the defence/​defense, the case for the prosecution, the merits of a case, carrying, packing, glass, in a/​the case, inside a/​the case, out of a/​the case, attaché, overnight, acute, chronic, advanced, diagnose, report, history, notes, records, case of
Antonymsexpansion, unfolding, openingsameness, uniformity
Common mistakesConfusing with 'capstone', which refers to a finishing stone., Using 'capsule' to refer to large containers., Mispronouncing with emphasis on the second syllable instead of the first.Confused with 'case' as a container instead of a situation., Using 'case' without properly specifying what type of case (e.g., legal case, medical case).
Usage notesUsed in medical contexts for pills and in general contexts for small containers. Avoid using in very casual settings.Use 'case' to refer to a particular situation, especially in legal or medical contexts. It is less formal than 'instance' and more common in everyday conversation.

Frequently asked questions: Capsule vs Case

What's the difference between Capsule and Case?

Capsule: A small container for medicine or other items. Case: A situation or example.

Which is more common: Capsule and Case?

Case is the most common in everyday English.

Are Capsule and Case the same CEFR level?

Capsule: C1, Case: A2 on the CEFR scale.

Can I use Capsule and Case interchangeably?

Not always. Capsule and Case are related and overlap in some contexts, but they differ in register, how common they are, and usage, so swapping one for another can change the meaning or tone. Check the differences above before substituting.

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