assure

If you assure your boss that you’ll finish your project by Tuesday, you are make a promise or commitment to have it done by Tuesday.

The verbs insure and ensure look and sound like assure but they aren't synonyms. There is some overlap in meaning — all of them can mean “to make secure or certain” — but assure is generally used in situations when you are referring to a person: “I assure you that I haven’t forgotten about driving you to the airport” or “He called his mother to assure her that everything will be fine.”

Definitions of assure
1

v inform positively and with certainty and confidence

Synonyms:
tell
Type of:
affirm, assert, aver, avow, swan, swear, verify
to declare or affirm solemnly and formally as true

v assure somebody of the truth of something with the intention of giving the listener confidence

“I assured him that traveling to Cambodia was safe”
Types:
reassure
give or restore confidence in; cause to feel sure or certain
Type of:
persuade
cause somebody to adopt a certain position, belief, or course of action; twist somebody's arm

v cause to feel sure; give reassurance to

Synonyms:
reassure
Antonyms:
vex, worry
disturb the peace of mind of; afflict with mental agitation or distress
worry
be worried, concerned, anxious, troubled, or uneasy
show more antonyms...
Type of:
calm, calm down, lull, quiet, quieten, still, tranquilize, tranquillise, tranquillize
make calm or still

v be careful or certain to do something; make certain of something

Synonyms:
ascertain, check, control, ensure, insure, see, see to it
check, check off, mark, mark off, tick, tick off
put a check mark on or near or next to
check
verify by consulting a source or authority
ascertain, check, determine, find out, learn, see, watch
find out, learn, or determine with certainty, usually by making an inquiry or other effort
control, verify
check or regulate (a scientific experiment) by conducting a parallel experiment or comparing with another standard
Types:
show 8 types...
hide 8 types...
proof, proofread
read for errors
control
verify by using a duplicate register for comparison
double-check
check once more to be absolutely sure
cross-check
check out conflicting sources; crosscheck facts, for example
cinch
make sure of
card
ask someone for identification to determine whether he or she is old enough to consume liquor
spot-check
pick out random samples for examination in order to ensure high quality
cover
maintain a check on; especially by patrolling
Type of:
verify
confirm the truth of

v make certain of

Synonyms:
ensure, guarantee, insure, secure
guarantee, vouch
give surety or assume responsibility
Types:
doom
make certain of the failure or destruction of
make
assure the success of

v make a promise or commitment

Synonyms:
promise
Types:
show 14 types...
hide 14 types...
pledge, plight
promise solemnly and formally
swear off
promise to abstain from
contract, undertake
enter into a contractual arrangement
guarantee, undertake
promise to do or accomplish
vow
make a vow; promise
stipulate
make an oral contract or agreement in the verbal form of question and answer that is necessary to give it legal force
sign
be engaged by a written agreement
subvent, subvention, underwrite
guarantee financial support of
guarantee, vouch
give surety or assume responsibility
condition, qualify, specify, stipulate
specify as a condition or requirement in a contract or agreement; make an express demand or provision in an agreement
covenant
enter into a covenant or formal agreement
lease, rent
let for money
charter, hire, lease, rent
hold under a lease or rental agreement; of goods and services
covenant
enter into a covenant
Type of:
declare
state emphatically and authoritatively

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