Many return to secure love seat (5)
I believe the answer is:
stool
'seat' is the definition.
(I know that seat can be written as stool)
'many return to secure love' is the wordplay.
'many' becomes 'lots' (I've seen this before).
'return' says the letters should be written in reverse.
'to secure' indicates putting letters inside (inserted letters are secured inside).
'love' becomes 'o' (love means zero in tennis).
'lots' written backwards gives 'stol'.
'stol' going around 'o' is 'STOOL'.
(Other definitions for stool that I've seen before include "Motion" , "Three-legged backless seat" , "Simple seat" , "item of furniture here" , "Armless seat" .)