The side piece of a door or window (4)
I believe the answer is:
jamb
(Other definitions for jamb that I've seen before include "part of doorway?" , "Side post of a doorway" , "Upright sidepiece" , "Upright of door" , "Doorpost" .)
I believe the answer is:
jamb
(Other definitions for jamb that I've seen before include "part of doorway?" , "Side post of a doorway" , "Upright sidepiece" , "Upright of door" , "Doorpost" .)