hummer

nouns

a singer who produces a tune without opening the lips or forming words
hummer
is derived from
hum
is a type of (narrower)
a person who sings
singer, vocaliser, vocalist, vocalizer
(baseball) a pitch thrown with maximum velocity
"he swung late on the fastball"; "he showed batters nothing but smoke"
bullet, fastball, heater, hummer, smoke