abrupt
/ə-ˈbrəpt/
adjective
characterized by or involving action or change without preparation or warning : sudden and unexpected
rudely or unceremoniously curt
lacking smoothness or continuity
came to an abrupt stop
She has an abrupt manner.
precipitate headlong abrupt impetuous sudden mean showing undue haste or unexpectedness. precipitate stresses lack of due deliberation and implies prematureness of action. headlong stresses rashness and lack of forethought.