One sworn to at home hides (4)
I believe the answer is:
oath
'one sworn' is the definition.
(I've seen this before)
'to at home hides' is the wordplay.
'hides' says the answer is hidden in the clue.
'OATH' is hidden within 'to at home'.
(Other definitions for oath that I've seen before include "Vow or expletive" , "Curse - sworn statement" , "Strong language" , "Swearword or solemn promise" , "gadzooks!" .)