noun, often capitalized, often attributive
\ ˈsē How to pronounce c (audio) \
plural c's or cs\ ˈsēz How to pronounce cs (audio) \

Definition of c

 (Entry 1 of 5)

1a : the 3rd letter of the English alphabet
b : a graphic representation of this letter
c : a speech counterpart of orthographic c
2a : one hundred — see Table of Numbers
b slang : a sum of $100
3 : the keynote of a C-major scale
4 : a graphic device for reproducing the letter c
5 : one designated c especially as the third in order or class
6a : a grade rating a student's work as fair or mediocre in quality
b : one graded or rated with a C
7 : something shaped like the letter C
8 : a structured language for creating computer programs that is designed to be compact and efficient

Definition of c (Entry 2 of 5)

1 calm
2 calorie
3 canceled
4 candle
5 canine (see canine entry 1 sense 1)
6 carat
7 catcher
8 cent
9 centavo
10 centi-
11 centime
12 centimeter
13 century
14 chapter
15 charm (see charm entry 1 sense 5)
16 circa
17 circumference
18 clonus
19 closure
20 cocaine
21 coefficient
22 college
23 [Latin congius] gallon
24 contralto
25 copyright
26 cubic
27 or [Latin cum] with used in writing prescriptions
28 cup
29 curie

Definition of c (Entry 3 of 5)

usually italic

Definition of C (Entry 4 of 5)

1 capacitance
2 Celsius
3 centigrade
4 cervical used especially with a number from 1 to 7 to indicate a vertebra or segment of the spinal cord
5 Coulomb
6 cytosine

Definition of C (Entry 5 of 5)


Examples of c in a Sentence

Noun The word “access” is spelled with two cs. Many English words begin with c. a song in the key of C
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First Known Use of c


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

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Time Traveler for c

Time Traveler

The first known use of c was before the 12th century

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Statistics for c

Cite this Entry

“C.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/c. Accessed 28 Oct. 2020.

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More Definitions for c

How to pronounce C (audio)

English Language Learners Definition of c

: the third letter of the English alphabet
: the Roman numeral that means 100
: a musical note or key referred to by the letter C : the first tone of a C-major scale


noun, often capitalized
\ ˈsē How to pronounce c (audio) \
plural c's or cs\ ˈsēz \

Kids Definition of c

1 : the third letter of the English alphabet
2 : the number 100 in Roman numerals
3 : a musical note referred to by the letter C
4 : a grade that shows a student's work is fair or average

Kids Definition of c.

1 carat
2 cent
3 centimeter
4 century
5 chapter
6 cup

Kids Definition of C

1 Celsius
2 centigrade

Medical Definition of c

 (Entry 1 of 3)

1 calorie
2 canine
3 cathode
4 centimeter
5 clonus
6 closure
7 cobalt
8 coefficient
9 contact
10 contraction
11 coulomb
12 curie
13 cylinder
14 or [Latin cum] with used in writing prescriptions

Medical Definition of C (Entry 2 of 3)

1 Celsius
2 centigrade
3 cervical used especially with a number from 1 to 7 to indicate a vertebra or segment of the spinal cord
4 cocaine
5 complement
6 congius
7 cytosine

Medical Definition of C (Entry 3 of 3)


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Legal Definition of c


More from Merriam-Webster on c

Nglish: Translation of c for Spanish Speakers

Comments on c

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