Free time absorbed by kids' bricks (3,2)
I believe the answer is:
let go
'free' is the definition.
(I've seen this in another clue)
'time absorbed by kids' bricks' is the wordplay.
'time' becomes 't' (abbreviation).
'absorbed by' is an insertion indicator.
'kids' bricks' becomes 'lego' (I've seen this before).
't' going within 'lego' is 'LET GO'.
(Other definitions for let go that I've seen before include "sack" , "Loose one's grip" , "Give up" , "Dismiss (from ones thoughts?)" , "Release or permit to depart" .)