The definition of before is something that happened before another thing, or something that was in front of or before another.
(adverb)Before is defined as a previous time.
(preposition)An example of before is when you are asked to do something prior to 7:00 PM.
See before in Webster's New World College Dictionary
adverb
Origin: ME biforen < OE beforan < be-, by + foran, fore
conjunction
See before in American Heritage Dictionary 4
adverb
Origin:
Origin: Middle English bifore
Origin: , from Old English beforan; see per1 in Indo-European roots
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