The definition of until is up to the time of, or before.(conjunction)
Until is defined as before a specific time.(preposition)
An example of until is when a student can't leave school until June 1st of a specific year, which is the scheduled last day of their senior year of school.
See until in Webster's New World College Dictionary
Origin: ME untill < un- (see unto) + till, to, till
See until in American Heritage Dictionary 4
Origin: Middle English
Origin: : un-, up to (from Old Norse und; see ant- in Indo-European roots)
Origin: + til, till; see till2.
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