1) an expression of contempt, disinterest, or
boredom, often used in the phrase "Well
la dee da" as a sarcastic "now isn't that amazing" or "good for you"
2) a phrase for singing, humming, mumbling etc. to
show joyful innocence
1)
Bob: You know what? I learned that the sky is blue today!
Bill: Well la dee da.
2) The little
girl skipped along singing "La dee da, what a wonderful
day!", until she was unfortunately run over by a garbage truck.