Taken Aback, Taken Back

Taken back is a corruption of taken aback, a long-standing idiom meaning "taken by surprise." Taken back properly means "to be returned." These days, however, taken back is used in statements like, "I was taken back by his rudeness." The snarky online Urban Dictionary cautions that taken back is a "phrase used by semi-educated morons who mean to say 'taken aback' when describing an event that left them disconcerted or abashed."