संगत या समस्वर होना या करना

harmonise(verb)

to sing or play musical instruments in harmony.

संगत देना

harmonise(verb)

to add different parts to (a melody) to form harmonies.

सामंजस्य स्थापित करना

harmonise(verb)

to (cause to) be in harmony or agreement

The colours in this room harmonize nicely.