Block H, a kick in the guts for the military (5)
I believe the answer is:
khaki
'for the military' is the definition.
(I've seen this before)
'block h a kick in' is the wordplay.
'in' says the answer is hidden in the clue.
'KHAKI' is hidden in the letters of 'block h a kick'.
'the guts' is the link.
This may not be correct. Some or all of it may belong to another bit of the clue.
Can you help me to learn more?
(Other definitions for khaki that I've seen before include "Uniform shade" , "Brownish-yellow" , "Dullish brown colour" , "military-type clothing" , "Yellowish brown (used by military)" .)