carefree and happy and lighthearted; "was loved for her blithe spirit"; "a merry blithesome nature"; "her lighthearted nature"; "trilling songs with a lightsome heart"
disapproval You use blithe to indicate that something is done casually, without serious or careful thought. It does so with blithe disregard for best scientific practice. + blithely blithe·ly Your editorial blithely ignores the hard facts