How to pronounce efficacy
Say it like EF-ih-kas-ee. Efficacy has four syllables, and the main stress falls on the first one (EF).
- EF
- ih
- kas
- ee
- Main stress
- Lighter stress
- Unstressed
Efficacy pronunciation, sound by sound
Read the parts left to right, then blend them together without pausing.
- EFSay this part loudest and longest. The vowel is the "e" in bed.
- ihKeep this part quick and light. The vowel is the "i" in sit.
- kasGive this part a little weight. The vowel is the "a" in cat.
- eeKeep this part quick and light. The vowel is the "ee" in see.
American vs British pronunciation of efficacy
American and British speakers say efficacy in essentially the same way: /ˈɛfɪˌkæsi/ in the US and /ˈɛfɪkəsi/ in the UK.
British respelling: EF-ih-kuh-see.
What does efficacy mean?
- capacity or power to produce a desired effect“concern about the safety and efficacy of the vaccine”
Where does efficacy come from?
From Old French efficace, from Late Latin efficācia (“efficacy”) (whence -acy), from efficāx (“efficacious”); see efficacious.
Questions about saying efficacy
How do you pronounce efficacy?
Say EF-ih-kas-ee. The American pronunciation is /ˈɛfɪˌkæsi/. In British English it is /ˈɛfɪkəsi/. Press play above to hear it at normal speed or slowly.
How many syllables are in efficacy?
Efficacy has four syllables, and the main stress falls on the first one (EF). Broken into parts: EF · ih · kas · ee.
Do Americans and Brits say efficacy the same way?
Almost exactly. The American form is /ˈɛfɪˌkæsi/ and the British form is /ˈɛfɪkəsi/, so you can use either pronunciation with any listener.