consciousness has 4 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. Its one recorded opposite is unconsciousness.
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.
an alert cognitive state in which you are aware of yourself and your situation
“he lost consciousness”
having knowledge of
“he had no awareness of his mistakes”
Synonyms, antonyms and the broader and narrower relations for consciousness come from Princeton University’s WordNet. Full sources and licences.