grogginess has 3 distinct synonyms spread across 1 of its 3 senses. Each sense below keeps its own list, because a synonym belongs to a meaning and not to a word: swapping one sense's substitute into another sense's sentence is how a thesaurus makes writing worse. WordNet records no antonym for it — antonymy is a relation between word forms rather than concepts, so it is deliberately sparse.
Counts are distinct word forms across every sense. A synonym that appears under three senses is counted once here and shown three times below, under each sense it belongs to.
a dazed and staggering state caused by alcohol
a groggy state resulting from weariness
marginal consciousness
“his grogginess was caused as much by exhaustion as by the blows”
Synonyms, antonyms and the broader and narrower relations for grogginess come from Princeton University’s WordNet. Full sources and licences.