Blindsided

Part of speech: adjective, verb

Definitions

1. Caught completely off guard by an unforeseen event or action
2. Experiencing a sudden surprise that disrupts expectations or plans
3. Taken by surprise in a way that leaves someone unprepared or shocked

Etymology: Blindsided is the past tense and past participle of "blindside," and the verb is simply a compound of "blind" and "side." The "blind" half traces back through Old English and Middle English to a Proto-Germanic root meaning unable to see, while "side" comes from Old English "sīde," an ordinary word for the flank of a body. The two words came together in English as a compound, with no borrowed or foreign pathway involved. The literal sense makes the modern meaning easy to follow. A blindside is the side of a person that they cannot see, the area they are not watching. A blow that lands there catches the body completely off guard, and the figurative sense of being caught completely unprepared grew directly from that physical image of an attack from a direction you did not expect.

Synonyms: surprised, caught off guard, unexpectedly attacked

Antonyms: prepared, forewarned, alert