To dilate is defined as to expand and become wider.(verb)
An example of dilate is when your eyes become wide with excitement.
See dilate in Webster's New World College Dictionary
Origin: ME dilaten < L dilatare < dis-, apart + latus, wide: see lateral
See dilate in American Heritage Dictionary 4
verb di·lat·ed, di·lat·ing, di·lates verb, transitive
Origin: Middle English dilaten
Origin: , from Old French dilater
Origin: , from Latin dīlātāre, to enlarge
Origin: : dī-, dis-, apart; see dis-
Origin: + lātus, wide.
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