Adjective blithe has 2 senses
  1. blithe - lacking or showing a lack of due concern; "spoke with blithe ignorance of the true situation"
    Antonym:
    concerned (indirect, via unconcerned)
  2. blithe, blithesome, lighthearted, lightsome - carefree and happy and lighthearted; "was loved for her blithe spirit"; "a merry blithesome nature"; "her lighthearted nature"; "trilling songs with a lightsome heart"
    Antonyms: cheerless, uncheerful (indirect, via cheerful)
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