The definition of colloquial refers to words or expressions used in ordinary language by common people.(adjective)
An example of colloquial is casual conversation where some slang terms are used and where no attempt is made at being formal.
See colloquial in Webster's New World College Dictionary
Origin: < L colloquium (see colloquy) + -al
See colloquial in American Heritage Dictionary 4
Origin: From colloquy.
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