The definition of sure is someone or something which is certain, trustworthy or always effective.(adjective)
An example of sure is someone who's positive they're getting a job for which they interviewed.
See sure in Webster's New World College Dictionary
Origin: OFr seur < L securus: see secure
See sure in American Heritage Dictionary 4
adjective sur·er, sur·est
Origin: Middle English
Origin: , from Old French, safe
Origin: , from Latin sēcūrus; see secure.
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