From Longman Dictionary of Contemporary Englishlisten for something phrasal verbLISTENto listen carefully so that you will notice a particular sound Listen for the moment when the music changes. → listen→ See Verb table
Examples from the Corpus
listen for • The men at the party were listening for guarantees that they will not be left unprotected.• The minutes dragged while they listened for the first hum of the approaching helicopter.• The first step is listening for the key issues and emotional concerns of community people.• He watches Julio listen for the sound and not hear it. 