confesar
/konfeˈsaɾ/ · B1 · verb
to confess, to come clean about
confesar = con + fess up: English confess with a Spanish -ar ending
From Latin confessus, from confiteri: con- (fully) + fateri (to admit, speak). Same root as English confess and profess. Swap the English ending for -ar and you have the Spanish verb.