falsetto

adj. (Music) of or pertaining to a falsetto; pertaining to an unnaturally high-pitched voice (esp. in a man); pertaining to one who sings with an unnaturally high-pitched voice (esp. of a man)

n. high-pitched voice of a man (Music); one who sings with such a voice

Falsetto (Italian diminutive of falso, false) is a singing technique that produces sounds that are pitched higher than the singer's normal range, in the treble range. The term is also used to describe a slightly artificially-raised sounding pitch that often occurs momentarily, if repeatedly, in boys during puberty as their voice changes.
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n. falsetto, (Music) pertaining to an unnaturally high-pitched voice

Noun
1. a male singing voice with artificially high tones in an upper register
(hypernym) head register, head voice, head tone
Adjective
1. artificially high; above the normal voice range; "a falsetto voice"
(similar) high, high-pitched