Synonyms for Happy:

adj.

beatific (adjective)
euphoric.
carefree (adjective)
at ease.
cheerful (adjective)
bright, merry, lively, cordial, amiable, easygoing, friendly, jaunty, buoyant, sparkling, lighthearted, joyful, cheerful, pleasant, sunny, happy-go-lucky, pleased, warm, genial, cheery, good-humored, spirited, glad, optimistic, jolly, agreeable, congenial, affable, complaisant.
content (adjective)
satisfied.
in high spirits; satisfied (adjective)
chipper, merry, cheerful, peaceful, content, light, blessed, playful, overjoyed, mirthful, jubilant, gratified, convivial, contented, gleeful, lively, pleased, glad, peppy, Tickled, perky, ecstatic, pleasant, elated, delighted, blissful, laughing, jolly, joyous, thrilled, sparkling, blithe, joyful, sunny, intoxicated, exultant.
lively (adjective)
animated.
pleasant (adjective)
delightful, blissful, euphoric, gratifying, likeable, cheerful, pleasurable, joyful, ecstatic, pleasant, exhilarating, satisfying.
rapturous (adjective)
rapturous.
suitable (adjective)
proper.

n.

amusing, roaring, shouting, alive, jesting, cheering, crying, festive, weeping, joking. lucky, season's greetings, Merry Christmas, luck, providential, many happy returns, happy birthday. fulfilled. pleasing. gala. becoming, appropriate, correct, meet, tailor-made, fitting, befitting, proper. happy (noun)
content, felicitous, golden, fortunate, elysian, blissful, prosperous, laughing, paradisial, paradisaic, riant, euphoric, well-chosen, pleased, blessed, halcyon, bright, joyous, paradisal, paradisiac, paradisaical, expansive, paradisiacal, euphoriant, contented, joyful.

Other synonyms:

comfortable, befitting, fit, gratified, Tickled, gladsome, content, intoxicated. right. animated
thrilled.
blissful
beatific.
captivated
enchanted.
convivial
jovial.
cordial
hearty.
enraptured
rapt, overjoyed.
exhilarated
elated.
exulting
exultant.
festive
gala.
frolicsome
playful.
high-spirited
exuberant.
in good spirits
chipper.
joyous
joyous, gleeful.
lighthearted
carefree.
merry
festive.
rejoicing
jubilant.
shining
radiant.
spirited
vivacious, animated.

Usage examples for happy

  1. Could she ever be happy again? – The Macdermots of Ballycloran by Anthony Trollope
  2. We were happy over there. – The Hollow of Her Hand by George Barr McCutcheon
  3. I can never be happy with you. – Dora Thorne by Charlotte M. Braeme