They're high-toned

• High parts
• Tiny Tim's notes
• Some doo-wop voices
• Female impersonators use them
• 1992 Broadway show that won Tonys for its book and score

Wikipedia Word definitions in Wikipedia
Falsettos is a musical with a book by James Lapine and William Finn and music and lyrics by Finn. The musical consists of March of the Falsettos and Falsettoland , the last two installments in a trio of one-act Off-Broadway musicals (the first was In Trousers ...

The Collaborative International Dictionary Word definitions in The Collaborative International Dictionary
Falsetto \Fal*set"to\, n.; pl. Falsettos . [It. falsetto, dim. fr. L. falsus. See False .] A false or artificial voice; that voice in a man which lies above his natural voice; the male counter tenor or alto voice. See Head voice , under Voice .

Wiktionary Word definitions in Wiktionary
n. (plural of falsetto English)