variants often F
plural f's or fs ˈefs How to pronounce f (audio)
often attributive
1
a
: the 6th letter of the English alphabet
b
: a graphic representation of this letter
c
: a speech counterpart of orthographic f
2
: the fourth tone of a C-major scale
3
: a graphic device for reproducing the letter f
4
: one designated f especially as the sixth in order or class
5
a
: a grade rating a student's work as failing
b
: one graded or rated with an F
6
: something shaped like the letter F

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Words Starting With F

Browse 14,184 words and phrases that start with the letter F, from fa to fytte.

Examples of f in a Sentence

The word “foot” begins with an f. The word “foot” begins with f. I got an F on the test.

Word History

First Known Use

before the 12th century, in the meaning defined at sense 1a

Time Traveler
The first known use of f was before the 12th century

Browse Nearby Words

Cite this Entry

“F.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/f. Accessed 11 Jun. 2026.

Kids Definition

f

noun
ˈef
plural f's or fs
often capitalized
1
: the sixth letter of the English alphabet
2
: a musical note referred to by the letter F : the fourth tone of a C-major scale
3
: a grade rating a student's work as failing

Medical Definition

f

1 of 4 abbreviation
1
farad
2
father
3
female
4
foot
5
formula

f

2 of 4 symbol
1
faraday
2
focal length
3
function

F

3 of 4 abbreviation
1
Fahrenheit
2
French

F

4 of 4 symbol
fluorine

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