to show (an act, claim, statement, etc.) to be just or right

The end does not always justify the means.

to defend or uphold as warranted or well-grounded

Don't try to justify his rudeness.

Theology . to declare innocent or guiltless; absolve; acquit.

Printing .

to make (a line of type) a desired length by spacing the words and letters, esp. so that full lines in a column have even margins both on the left and on the right.

to level and square (a strike).

Law .

to show a satisfactory reason or excuse for something done.

to qualify as bail or surety.

Printing . (of a line of type) to fit exactly into a desired length.

verb

absolve , acquit , advocate , alibi * , answer for , apologize for , approve , argue for , assert , be answerable for , bear out , brief , claim , clear , condone , confirm , contend , cop a plea , countenance , crawl , defend , do justice to , establish , exculpate , excuse , exonerate , explain , favor , legalize , maintain , make allowances , make good , palliate , pardon , plead , rationalize , rebut , show cause , speak in favor , square , stand up for , support , sustain , uphold , validate , verify , vindicate , warrant , call for , occasion , attest , authenticate , back , corroborate , evidence , substantiate , testify , apologize , account for , accept , account , authorize , exonorate , justify , legitimate , legitimize , permit , sanction