Meaning: 1. containing, or resembling yeast, 2. lacking in seriousness or maturity.
Synonyms: barmy, creamy, fizzy, seething, spumy, burbling, dizzy, featherbrained, flighty, frivolous, frothy
Antonyms: earnest, serious, serious-minded, sober, unfrivolous
Usage/Example: 1. This pale gold, slightly hazy Belgian pale ale offers yeasty, banana candy, dried fruit and malty notes on the nose (Source: Winnipeg Free Press)
2. The mixture should smell a little bit yeasty when ready
3. The warm, floral-yeasty air flows out in waves, wafting around the rows and rows of barrels. (Source: Eater)