[Echoic. Cf. WOOF sb.2, WOUGH sb., and next.] A low, suppressed bark of a dog.

1

1824.  [Carr], Craven Gloss., s.v.

2

1888.  ‘J. S. Winter,’ Bootle’s Childr., ii. The ‘wuff-wuff’ of one or other of the dogs breaking the silence.

3