BLITHELY
happily, merrily, mirthfully, gayly, blithely, jubilantly
(adverb) in a joyous manner; “they shouted happily”
Source: WordNet® 3.1
Etymology
Adverb
blithely (comparative more blithely, superlative most blithely)
Without care, concern, or consideration.
Synonyms: carelessly, indifferently
In a joyful, carefree manner.
Synonyms: gladly, joyfully, merrily
(obsolete) In a kind manner.
Source: Wiktionary
Blithe"ly, adv.
Definition: In a blithe manner.
BLITHE
Blithe, a. Etym: [AS. bli blithe, kind; akin to Goth. blei kind,
Icel. bli mild, gentle, Dan. & Sw. blid gentle, D. blijd blithe, OHG.
blidi kind, blithe.]
Definition: Gay; merry; sprightly; joyous; glad; cheerful; as, a blithe
spirit.
The blithe sounds of festal music. Prescott.
A daughter fair, So buxom, blithe, and debonair. Milton.
Source: Webster’s Unabridged Dictionary 1913 Edition