TO TAKE ABACK, verb. phr. (colloquial).To surprise; to check: suddenly and forcibly. [Orig. nautical: in which sense (O.E.D.) dating from 1754.]
1840. HOOD, Up the Rhine, 21. The boy, in sea phrase, was TAKEN ALL ABACK.
1842. DICKENS, American Notes, 52. I dont think I was ever so TAKEN ABACK in all my life.
1878. BOSWORTH SMITH, Carthage, 95. For the moment TAKEN ABACK by the strange appearance.