Suspicion about monarch in domestic row? (7)
I believe the answer is:
terrace
'domestic row?' is the definition.
(row of houses)
'suspicion about monarch' is the wordplay.
'suspicion' becomes 'trace' (suspicion can mean a small trace).
'about' indicates putting letters inside.
'monarch' becomes 'ER' (abbreviation for Elizabeth Regina, British Queen).
'trace' enclosing 'er' is 'TERRACE'.
'in' is the link.
(Other definitions for terrace that I've seen before include "Stadium standing area" , "From which spectators watch" , "steps in stadium" , "Row of attached houses" , "street" .)