be on the lookout for

idiom
variants: or keep a lookout for

Definition of be on the lookout for

: to watch or search for (something or someone) : be alert to Be on the lookout for flooded roads after heavy rainstorms. The police officer walked through the neighborhood, keeping a (sharp) lookout for any suspicious activity.

More from Merriam-Webster on be on the lookout for

Thesaurus: All synonyms and antonyms for be on the lookout for

Comments on be on the lookout for

What made you want to look up be on the lookout for? Please tell us where you read or heard it (including the quote, if possible).

WORD OF THE DAY

to engage in dissolute behavior

Get Word of the Day daily email!

Test Your Vocabulary

Pass the Little Ribbons: A Pasta Word Quiz

  • rotelle pasta
  • Match the pasta to its meaning in English: Rotelle
Spell It

Can you spell these 10 commonly misspelled words?

TAKE THE QUIZ
Bee Cubed

Test Your Knowledge - and learn some interesting things along the way.

TAKE THE QUIZ
Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!