phut

Imitative.

phut

1. A sound resembling the release of a blast of steam or exhaust gas.
   • 1980, Gillian Cooke, A Celebration of Christmas

     Even an expensive cracker can go off with a phut, not a bang, and burst to reveal one paper hat, one tired motto and a piece of plastic jewellery.

   • 2007, Susan Gates, Beyond the Billboard

     Then she heard the phut-phut-phut of an unfamiliar boat engine.

phut (third-person singular simple present phuts, present participle phutting, simple past and past participle phutted)

1. To produce such a sound.