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Co

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Symbol, Chemistry.
cobalt.
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Other definitions for Co (2 of 9)

CO

abbreviation
Colorado (approved especially for use with zip code).

Other definitions for Co (3 of 9)

co-

variant of com- before a vowel, h, and gn:coadjutor; cohabit; cognate. The prefix co- now productively forms new words from bases beginning with any sound (co-conspirator; co-manage; coseismic), sometimes with the derived sense “auxiliary, subsidiary” (coenzyme; copilot), and, in mathematics and astronomy, with the sense “complement” (codeclination).

Other definitions for Co (4 of 9)

c/o

care of.
Bookkeeping. carried over.
cash order.

Other definitions for Co (5 of 9)

c.o.

abbreviation
care of.
carried over.

Other definitions for Co (6 of 9)

Co.

or co.


abbreviation
Company.
County.

Other definitions for Co (7 of 9)

C/o

care of.
Bookkeeping. carried over.

Other definitions for Co (8 of 9)

C/O

cash order.
certificate of origin.

Other definitions for Co (9 of 9)

C.O.

abbreviation
cash order.
Commanding Officer.
conscientious objector.
correction officer.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2021

How to use Co in a sentence

British Dictionary definitions for Co (1 of 7)

co

the internet domain name for
a commercial company (used with a country domain name)
Colombia

British Dictionary definitions for Co (2 of 7)

Co1

the chemical symbol for
cobalt

British Dictionary definitions for Co (3 of 7)

Co2

abbreviation for
County

British Dictionary definitions for Co (4 of 7)

Co3

co


abbreviation for
(esp in names of business organizations) Company
and co (kəʊ) informal and the rest of themHarold and co

British Dictionary definitions for Co (5 of 7)

CO

abbreviation for
Commanding Officer
Commonwealth Office
conscientious objector
Colorado
Colombia (international car registration)

British Dictionary definitions for Co (6 of 7)

co-

prefix
together; joint or jointly; mutual or mutuallycoproduction
indicating partnership or equalitycofounder; copilot
to the same or a similar degreecoextend
(in mathematics and astronomy) of the complement of an anglecosecant; codeclination

Word Origin for co-

from Latin, reduced form of com-

British Dictionary definitions for Co (7 of 7)

c/o

abbreviation for
care of
accounting carried over
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Medical definitions for Co (1 of 3)

Co

The symbol for the elementcobalt

Medical definitions for Co (2 of 3)

CO

abbr.
cardiac output

Medical definitions for Co (3 of 3)

co-

pref.
Together; joint; jointly; mutually:coaptation.
Subordinate or auxiliary:coenzyme.
To the same extent or degree:codominant.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.

Scientific definitions for Co

Co

The symbol for cobalt.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
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