take someone aback

take (one) aback

To startle, astonish, shock, or disconcert one. It took us all aback a bit to learn that John was moving to England next month. I'm sure the news of the merger takes everyone aback, but please believe me that this is in the best interest of the company.
See also: aback, take
Farlex Dictionary of Idioms.

take someone aback

shock, surprise, or disconcert someone.
The phrase is frequently used in the passive form (be taken aback ): this was adopted in the mid 19th century from earlier (mid 18th-century) nautical terminology, to describe the situation of a ship with its sails pressed back against the mast by a headwind, preventing forward movement.
1991 Kathleen Jones Learning Not To Be First They were taken aback by the shabbiness of the hotel and lack of cleanliness in the city generally.
See also: aback, someone, take
Farlex Partner Idioms Dictionary
See also:
  • take (one) aback
  • take aback
  • taken aback
  • set (one) aback
  • aback
  • be set aback
  • be taken aback
  • surprise (one) by (doing) (something)
  • surprise by
  • surprise (one) with (something)