Precaution
late 16th century (in the sense ‘prudent foresight’): from French précaution, from late Latin praecautio(n- ), from Latin praecavere, from prae ‘before’ + cavere ‘take heed, beware of’.
wiktionary
From French précaution, Latin praecautio, from praecavere, praecautum(“to guard against beforehand”); prae(“before”) + cavere(“be on one's guard”). See pre-, and caution.
etymonline
precaution (n.)
"previous caution, prudent foresight (to prevent mischief or secure good results); a measure taken beforehand, an act of foresight," c. 1600, from French précaution (16c.) and directly from Late Latin praecautionem (nominative praecautio) "a safeguarding," noun of action from past-participle stem of Latin praecavere "to guard against beforehand," from prae "before" (see pre-) + cavere "to be one's own guard" (see caution (n.)). In mid-20c. a euphemism for "contraception." The verb meaning "to warn (someone) in advance" is from c. 1700.
