from
The Collaborative International Dictionary of English v.0.48
Warble \War"ble\, v. t. [imp. & p. p. {Warbled}; p. pr. & vb. n.
{Warbling}.] [OE. werbelen, OF. werbler; of Teutonic origin;
cf. G. wirbeln to turn, to warble, D. wervelen, akin to E.
whirl. See {Whirl}.]
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1. To sing in a trilling, quavering, or vibratory manner; to
modulate with turns or variations; to trill; as, certain
birds are remarkable for warbling their songs.
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2. To utter musically; to modulate; to carol.
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If she be right invoked in warbled song. --Milton.
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Warbling sweet the nuptial lay. --Trumbull.
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3. To cause to quaver or vibrate. "And touch the warbled
string." --Milton.
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