whir
1. [ verb ] make a soft swishing sound, as of a motor working or wings flapping
Synonyms: whiz birr whirr purr whizz
Related terms: go whiz
2. [ noun ] sound of something in rapid motion
Synonyms: whirring birr whirr
Examples:

: "whir of a bird's wings" "the whir of the propellers"

Related terms: sound whizz
Similar spelling:   whirr
  whore
  where
  wherry