whereat Meaning, Definition & Usage

Where*at" adverb
Definitions
  1. At which; upon which; whereupon; -- used relatively.
    They vote; whereat his speech he thus renews. Milton.
    Whereat he was no less angry and ashamed than desirous to obey Zelmane. Sir P. Sidney.
  2. At what; -- used interrogatively; as, whereat are you offended?

Webster 1913