uptake has 3 distinct synonyms spread across 1 of its 2 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.
the process of taking food into the body through the mouth (as by eating)
Synonyms, antonyms and the broader and narrower relations for uptake come from Princeton University’s WordNet. Full sources and licences.
a process of taking up or using up or consuming
“they developed paper napkins with a greater uptake of liquids”