This is a regular verb. It follows the conjugation pattern of the verb falar.
Present:
A música abafa o barulho da rua.
The music drowns out the street noise.
Preterite:
Ele abafou o escândalo.
He covered up the scandal.
Imperative:
Abafe as chamas com um cobertor.
Abafa as chamas com uma manta.
Smother the flames with a blanket.