What does "on accident" mean?

Accidentally; not intentionally; because of error, misfortune, or lack of caution.

What is a synonym for "on accident"?

Common synonyms include: accidentally.

adv

adv ·Rare ·Advanced level

Adverb

1
Accidentally; not intentionally; because of error, misfortune, or lack of caution. proscribed
"I'm sure he backed into the hedge on accident, but the hedge and the car are both a mess now."

"I'm sure he backed into the hedge on accident, but the hedge and the car are both a mess now."