Dad exploits them as delays (4)
I believe the answer is:
uses
'dad exploits' is the definition.
'uses' can be an answer for 'exploits' (use is a kind of exploit). I'm not certain of the 'dad' bit.
I don't understand how the rest of the clue works.
Can you help me to learn more?
(Other definitions for uses that I've seen before include "Customs" , "Functions, applications" , "deployments" , "Puts into service" , "Employs" .)