to establish the truth, accuracy, validity, or genuineness of; corroborate; verify

This report confirms my suspicions.

to acknowledge with definite assurance

Did the hotel confirm our room reservation?

to make valid or binding by some formal or legal act; sanction; ratify

to confirm a treaty; to confirm her appointment to the Supreme Court.

to make firm or more firm; add strength to; settle or establish firmly

Their support confirmed my determination to run for mayor.

to strengthen (a person) in habit, resolution, opinion, etc.

The accident confirmed him in his fear of driving.

to administer the religious rite of confirmation to.

verb

annul , cancel , contradict , destroy , disprove , invalidate , oppose , veto , void , deny , repudiate , abrogate

verb

affirm , approve , attest , authenticate , back , bear out , bless , buy , certify , check , check out , circumstantiate , corroborate , debunk , double-check , endorse , establish , explain , give green light , give high sign , give stamp of approval , give the go-ahead , give the nod , justify , lap up , make good , make sure , okay , rubber-stamp , sanction , settle , sign , sign off on , size up , subscribe , substantiate , support , thumbs up * , underpin , uphold , verify , vouch , warrant , witnessnotes:corroborate is used in a narrower context , usually by way of providing support for testimony in a legal proceeding; confirm is to lend support to a much wider array of things , assure , buttress , clinch , fix , fortify , invigorate , make firm , strengthennotes:corroborate is used in a narrower context , evidence , testify , validate , demonstrate , show , harden , strengthen , adopt , pass , ratify , approbate , confirm , countersign , firm , prove , reinforce , satisfy , seal , sustain , vouch for