Antonyms for gloom

melancholy, depression:

comfort, light, brightness, animation, sunniness, contentedness, confidence, vivaciousness, trust, hopefulness, joy, cheer, gladness, pleasure, cheerfulness, contentment, joyfulness, encouragement, sparkle, delight, happiness.

noun:

sunniness, exuberance, brilliance, joyousness, starlight, moonlight, brightness, jubilation, optimism, lightness, content, hopefulness, rapturousness, luminousness, sunlight, radiancy, joyfulness, daylight, gladsomeness, felicity, day, sunshine, humor, exultation, lightheartedness, luminosity, effulgence.