verb
assure
uh-SHAW
verb
1
To tell someone something confidently in order to remove their doubt or worry.
"The mechanic assured us the car was safe to drive."
"She assured her parents she would call as soon as she landed."
2
To make something certain to happen; to guarantee it.
"A strong defense assured the team’s victory."
"Careful planning assures a smooth launch."
How to Use Assure
Learner’s notesIn plain EnglishTo tell someone confidently that something is true or will happen, so they stop worrying, or to make an outcome certain.
Common mistake
Don’t confuse with "ensure" (to make certain something happens) or "insure" (to protect financially against loss) — British English especially distinguishes assure/insure for life insurance versus ensure for guaranteeing outcomes.
Easily confused with
ensure →
insure
Common pairings
assure someone that
rest assured
assure safety
Word Forms
assured past tense, assures singular
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The mechanic _____ us the car was safe to drive.
Etymology
From Old French asseurer, ultimately from Latin ad- (\"to\") plus securus (\"secure\") — the same root that gives us \"secure\" and \"security.\"