whirr
n 1: sound of something in rapid motion; "whir of a bird's
wings"; "the whir of the propellers" [syn: {whir}, {whirr},
{whirring}, {birr}]
v 1: make a soft swishing sound; "the motor whirred"; "the car
engine purred" [syn: {whizz}, {whiz}, {whirr}, {whir},
{birr}, {purr}]
2: make a vibrant sound, as of some birds [syn: {churr},
{whirr}]