flabbergast

surprise, astonish, astound, amaze, flabbergast mean to impress forcibly through unexpectedness. surprise stresses causing an effect through being unexpected but not necessarily unusual or novel <surprised to find them at home>. astonish implies surprising so greatly as to seem incredible <a discovery that astonished the world>. astound stresses the shock of astonishment <too astounded to respond>. amaze suggests an effect of bewilderment <amazed by the immense size of the place>. flabbergast may suggest thorough astonishment and bewilderment or dismay <flabbergasted by his angry refusal>.