What does "heads up" mean?

Alternative spelling of heads-up.

Heads up

Common synonyms include: alert, fore, note capture method, save material, surface plane stock, tipoff.

adj, intj, noun, verb

adj, intj, noun, verb ·Rare ·Advanced level

Noun

Verb

1
third-person singular simple present indicative of head up form-of, indicative, present, singular, third-person

Adjective

Intj

1
Used as an informal warning, caution, or call for attention; pay attention! idiomatic
"Heads up! I'm about to let go."

"Heads up, Marines! We got trouble."