co

1 of 5

abbreviation (1)

1
company
2
county

Co

2 of 5

symbol

cobalt

CO

3 of 5

abbreviation (2)

1
cash order
2
Colorado
3
commanding officer
4
conscientious objector
5
corrections officer

c/o

4 of 5

abbreviation (3)

care of

co-

5 of 5

prefix

1
: with : together : joint : jointly
coexist
coheir
2
: in or to the same degree
coextensive
3
a
: one that is associated in an action with another : fellow : partner
coauthor
coworker
b
: having a usually lesser share in duty or responsibility : alternate : deputy
copilot
4
: of, relating to, or constituting the complement of an angle
cosine

Word History

Etymology

Prefix

borrowed from Latin, variant of com- before a vowel, h, and gn — more at com-

Note: The original distribution of co- and com- with its variants has been lost in English and co- is now used before words beginning with any sound, especially in senses 3a and b.

Dictionary Entries Near co

Co

co

CO

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Cite this Entry

“Co.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/co. Accessed 29 Nov. 2024.

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Kids Definition

co-

prefix
1
: with : together : joint : jointly
coexist
coauthor
2
: in or to the same degree
coextensive
3
: fellow : partner
coworker
Etymology

Prefix

derived from Latin com- "with, together"

Medical Definition

Co

1 of 4 abbreviation
coenzyme

Co

2 of 4 symbol
cobalt

CO

3 of 4 abbreviation
cardiac output

c/o

4 of 4 abbreviation
complains of

Legal Definition

c/o

1 of 4 abbreviation
care of

co

2 of 4 abbreviation
1
company
2
county

CO

3 of 4 abbreviation
1
commanding officer
2
conscientious objector
3
corrections officer

co-

4 of 4 prefix
1
: with : together : joint : jointly
codefendant
2
a
: associated in an action with another : fellow
co-conspirator
b
: having a usually lesser share in duty or responsibility : alternate : deputy
co-counsel

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