English▸ verb [no object] (of a bird) sing softly and with a succession of constantly changing notes:
larks were warbling in the trees.
▪ (of a person) sing in a trilling or quavering voice:
he warbled in an implausible soprano.
▸ noun a warbling sound or utterance:
through the wall came a faint warble
the warble of the phone.
– ORIGIN late Middle English (as a noun in the sense ‘melody’): from Old Northern French werble (noun), werbler (verb), of Germanic origin; related to whirl.