The definition of c/o is the abbreviation for care of or cash order.(abbreviation)
An example of c/o is what you write along with a name as the first line in an address on an envelope when the person to whom you are sending the letter is not a known resident at the address.
The definition of co means together, partner, assistant, equally or jointly.(prefix)
See co in Webster's New World College Dictionary
Origin: var of com-, orig. occurring only before a vowel, h, or gn
See co in American Heritage Dictionary 4
Origin: Middle English
Origin: , from Latin
Origin: , variant of com-, com-.
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