yodel

v. sing high-pitched falsetto song of Swiss and Tyrolese mountaineers

n. falsetto-pitched song of Swiss and Tyrolean mountaineers; yodeling cry or call

Yodeling (or yodelling, jodeling) is a form of singing that involves singing an extended note which rapidly and repeatedly changes in pitch from the vocal chest register (or "chest voice") to the head register (or "head voice"), making a high-low-high-low sound. This vocal technique is used in many cultures throughout the world.
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Noun
1. a songlike cry in which the voice fluctuates rapidly between the normal voice and falsetto
(hypernym) cry, outcry, call, yell, shout, vociferation
(derivation) warble, descant
Verb
1. sing by changing register; sing by yodeling; "The Austrians were yodeling in the mountains"
(synonym) warble, descant
(hypernym) sing
(derivation) yodeller

(v. t. & i.)
Alt. of Yodle
  

(n.)
Alt. of Yodle
  

doyle