blithe


blithe (http://definr.com/blithe)

     adj 1: lacking or showing a lack of due concern; "spoke with blithe
            ignorance of the true situation"
     2: carefree and happy and lighthearted; "was loved for her
        blithe spirit"; "a merry blithesome nature"; "her
        lighthearted nature"; "trilling songs with a lightsome
        heart" [syn: blithesome, lighthearted, lightsome]