goofy

Synonyms

birdbrained, ditzy (or ditsy), dizzy, featherbrained, flighty, frivolous, frothy, giddy, harebrained, light-headed, light-minded, puerile, scatterbrained, silly;

Antonyms

earnest, serious, serious-minded, sober;

Near Antonyms

grave, melancholy, somber (or sombre), thoughtful;

dignified, heavy, no-nonsense, sedate, severe, solemn, staid;

Related Words

fatuous, foolish, inane, nonsensical, witless;

crazy, daffy, daft, fruity;

flippant, fluttery, giggly, happy, light, lighthearted, playful;

sappy, shallow, superficial;