Cutter, when returned, secured by husband and wife (7)
I believe the answer is:
handsaw
'cutter' is the definition.
(I know that handsaw is a type of saw)
'when returned secured by husband and wife' is the wordplay.
'when' becomes 'as' (eg 'when I walked' means 'as I walked').
'returned' says the letters should be written in reverse.
'secured by' indicates putting letters inside (inserted letters are held or secured).
'husband' becomes 'h' (abbreviation).
'wife' becomes 'w' (abbreviation).
'as' in reverse letter order is 'sa'.
'h'+'and'+'w'='handw'
'sa' inserted inside 'handw' is 'HANDSAW'.
(Other definitions for handsaw that I've seen before include "wood tool" , "cutting tool" , "Manual tool" , "Manual cutter" .)