wah-wah adjective 1exclamation 1noun 1verb 1forms 3 adjective1 •Modifying the resonance of musical notes to produce the effect of a human voice. exclamation1 •(US, Canada) The sad trombone sound, used to indicate failure or disappointment, often used mockingly.When told during a Fox News segment about a 10-year-old with Down syndrome who was separated from her mother at the southern border, the former campaign manager of President Trump replied, "Wah wah." — 2018 noun1 •A wavering sound produced by means of a movable mute or by electronic means. verb1 •To make a wah-wah sound. formswah-wahed · wah-wahing · wah-wahs