Synonyms for Sunny side up:

• adj.

  •cheerful (adjective)
  • bucked,
  • sparkling,
  • jocund,
  • high,
  • up,
  • good-humored,
  • chirpiest,
  • perky,
  • upbeat,
  • gay,
  • blithe,
  • chirpier,
  • glad,
  • zappy,
  • full of pep,
  • hopeful,
  • zingy,
  • winsome,
  • roseate,
  • hilarious,
  • optimistic,
  • good-natured,
  • in high spirits,
  • enlivening,
  • bouncy,
  • sunny,
  • up-beat,
  • merry,
  • gladsome,
  • snappy,
  • lively,
  • vivacious,
  • joyful,
  • in good spirits,
  • lighthearted,
  • contented,
  • sprightly,
  • zippy,
  • hearty,
  • heartiest,
  • cheery,
  • peppy,
  • bright,
  • pleasant,
  • airy,
  • jaunty,
  • sanguine,
  • buoyant,
  • animated,
  • rosy,
  • jolly,
  • chipper,
  • chirpy,
  • effervescent,
  • enthusiastic.
  •genial (adjective)
  • friendly,
  • gracious,
  • jovial,
  • kind,
  • sociable,
  • amiable,
  • favorable,
  • convivial,
  • cheering,
  • upper,
  • easygoing,
  • agreeable,
  • joyous,
  • neighborly,
  • warm,
  • amicable,
  • congenial,
  • kindly,
  • gentle,
  • affable,
  • cordial.

• Other synonyms:

  •adj.
  • cheerful,
  • genial,
  • Warm-hearted.

Antonyms for Sunny side up:

• adj.

  • cheerful
    upset, hopeless, lethargic, down, pale, cheerless, lifeless, pessimistic, dull, sorrowful, unhappy, heavy, sad, depressing, inactive, unenthusiastic, serious, cloudy, grave, apathetic, gloomy, melancholy, heavy-hearted, depressed.
  • genial
    mean, cool, surly, nasty, rude, unfriendly, unsympathetic, moody, cranky, hateful, cold, irritable, disagreeable, aloof, unkind.
  • joyful/joyous
    woeful.
  • light
    dim, laborious, difficult, boring, brunette, solemn, dark, unfunny, obscure, weighted, dusky, black, darkened, tiring.