tra-la
Blithe vocal filler
Tra-la is a lighthearted vocalization suggesting carefree singing or humming, often used to convey cheerfulness or dismissiveness.
It appears in phrases like tra-la-la to represent the sound of someone singing without words, typically while going about their business in a breezy or unconcerned manner.
The expression can also be used sarcastically to mock excessive cheerfulness or to brush off something unpleasant.
vocalize
Produce sounds aloud
croon · lilt · carol · serenade · chorus · refrain · ditty · melody · tune · jingle
joyful
Feeling great happiness
lighthearted · buoyant · sunny · gleeful · jovial · chipper · bubbly · effervescent · sprightly · jaunty
hooray
Exclamation of delight
heigh-ho · yo-ho · fol-de-rol