Unawares (adverb)

Without being aware or expecting something; unexpectedly.

Origin:

From the word aware meaning "having knowledge or perception" and the prefix un- meaning "not".

Examples:

1. He was caught unawares by the sudden question.
2. She was taken unawares by the news of the pregnancy.
3. The company was caught unawares by the economic downturn.
4. He was surprised unawares by the birthday party.
5. She was attacked unawares while walking home late at night.