In search of the sound of some laughter (5)

I believe the answer is:

after

I'm a little stuck... Click here to teach me more about this clue!

'in search' is the definition.
(I've seen this in other clues)

I don't understand how the rest of the clue works.

(Other definitions for after that I've seen before include "Pursuing" , "Coming later in time" , "In the time following" , "Looking for" , "In pursuit of, behind" .)

I've seen this clue in the Evening Standard.

Want a hint initially instead of a full solution? Install my app