SAT earnest Definition Serious in intention or purpose; showing sincerity. Example "He made an earnest promise to return the borrowed money." Sign in to save SAT Quiz → ← eager earring → Study tips featuring "earnest" Spot the Vocabulary Trap in Every Question How Context Clues Save You on the SAT Related words SAT abase SAT abdicate SAT abdomen SAT abduction SAT abet SAT abeyance SAT abject SAT abjure SAT ablution SAT abnegate SAT abnormal SAT abominable