What does ef mean?
"Ef" is the conventional English name for the letter F, one of the twenty-six letters of the Latin alphabet as used in English. Like most letter names, it functions as an ordinary noun despite being essentially a label for itself: it can be counted ("two efs"), pluralized, and discussed like any other word. It appears chiefly in situations where letters are named rather than read silently — spelling words aloud, teaching children the alphabet, transcribing dictation, or referring to typographic and linguistic matters. The plural is usually written "efs" or sometimes "effs." Because the letter F carries strong associations in slang, the homophonous spelling "eff" is often preferred when writers want to allude to profanity indirectly. Beyond such special uses, "ef" is a modest but genuinely useful word, reminding us that even the alphabet's individual characters have their own names, histories, and dictionary entries.
nounThe name of the fifth letter of the modern English alphabet, written "F" in uppercase and "f" in lowercase.
- The name of the letter F, the sixth letter of the English alphabet (counting A as first).
- The spoken sound /ɛf/ represented by this letter, as when sounding out letters individually.
"In the phonetic alphabet exercise, the teacher asked the class to circle every ef they could find on the page."
""Ef," she said slowly, sounding out each letter for the beginner reader."
"The acronym was spelled out letter by letter: em, ef, kay."
Both "efs" and "effs" are acceptable plurals; "effs" is common in informal writing that also plays on the euphemistic sense of "eff."
"There were three long efs in the word she was trying to pronounce."
It's one of the rare words whose entire job is to spell itself — "ef" is how you say the letter F out loud.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of ef
The name "ef" descends directly from Latin, where the letter F was called "ef." Latin itself borrowed both the letterform and its naming convention from earlier alphabets, ultimately tracing back through Etruscan and Greek to the Phoenician letter waw. When English adopted the Latin alphabet, it inherited the pronunciation of the letter's name essentially unchanged, so "ef" has been the stable English name of F for many centuries.
Related word forms
How ef is actually used
"Ef" is almost always encountered as the spoken form of the letter rather than as a written word; it appears mainly in contexts involving spelling aloud, teaching reading, or discussing letters themselves.
Easily confused with ef
"Eff" is an informal euphemistic spelling used to represent or allude to the F-word without saying it, while "ef" is simply the neutral name of the letter F.