Render harmless in lunar module (5)
I believe the answer is:
unarm
'render harmless' is the definition.
(synonyms)
'in lunar module' is the wordplay.
'in' says the answer is hidden in the clue.
'UNARM' is hidden within 'lunar module'.
(Other definitions for unarm that I've seen before include "Remove weapons from" , "Neutralise defence" , "Take weapons from (someone)" , "Render harmless" , "Take weapon" .)