It's not part of SOS (3)
I believe the answer is:
our
(Other definitions for our that I've seen before include "group possession?" , "'-- House' (Madness song)" , "Yours and mine" , "Relating to us" , "Belonging to us" .)
I believe the answer is:
our
(Other definitions for our that I've seen before include "group possession?" , "'-- House' (Madness song)" , "Yours and mine" , "Relating to us" , "Belonging to us" .)