Synonyms for Sour (same or very similar meaning)
WordNet sense 1 (the taste experience when vinegar or lemon juice is taken into the mouth):
sourness, tartness
WordNet sense 2 (the property of being acidic):
acidity
WordNet sense 3 (pleasing to the sense of taste):
tasty
WordNet sense 4 (in an unpalatable state):
off, turned
WordNet sense 5 (having turned bad):
soured
WordNet sense 6 (tasting sour like a lemon):
tart
WordNet sense 7 (being sour to the taste):
acid
WordNet sense 8 (tasting or smelling like vinegar):
vinegary, acetous, acetose, vinegarish
WordNet sense 9 (make sour or more sour):
acidify, acetify, acidulate
WordNet sense 10 (showing a brooding ill humor):
dark, dour, glowering, glum, moody, morose, saturnine, sullen
WordNet sense 11 (having an irritable and unpleasant disposition):
ill-natured
WordNet sense 12 (smelling of fermentation or staleness):
rancid
WordNet sense 13 (having an unpleasant smell):
malodorous, stinky, malodourous, ill-smelling, unpeasant-smelling
WordNet sense 14 (inaccurate in pitch):
off-key, false
WordNet sense 15 (not in harmony):
inharmonious, unharmonious
WordNet sense 16 (go sour or spoil):
ferment, turn, work, ferment
From the ODE community, based on WordNet
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