[abrupt] adj [L abruptus, fr. pp. of abrumpere to break off, fr. ab- + rumpere to break--more at reave] (1591) 1 a: characterized by or involving action or change without preparation or warning: unexpected "came to an ~ stop" "an ~ turn to the left" "an ~ decision to retire" b: unceremoniously curt "an ~ manner" c: lacking smoothness or continuity "an ~ transition"
2: giving the impression of being cut or broken off; esp: involving a sudden steep rise or drop "~ hills" "a high ~ bank bounded the stream" syn see precipitate, steep -- abrupt.ly adv -- abrupt.ness n