"How's it goin'?” (3)
I believe the answer is:
sup
'how's it goin'?' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for sup that I've seen before include "Eat a late meal; sip" , "Drink; take a late meal" , "Drink; eat evening meal" , "Drink; take an evening meal" , "Imbibe" .)