perception has 3 distinct synonyms spread across 2 of its 5 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 representation of what is perceived; basic component in the formation of a concept
a way of conceiving something
“Luther had a new perception of the Bible”
the process of perceiving
knowledge gained by perceiving
“a man admired for the depth of his perception”
Synonyms, antonyms and the broader and narrower relations for perception come from Princeton University’s WordNet. Full sources and licences.