profess has 3 distinct synonyms spread across 2 of its 7 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.
practice as a profession, teach, or claim to be knowledgeable about
“She professes organic chemistry”
confess one's faith in, or allegiance to
“The terrorists professed allegiance to their country”
admit (to a wrongdoing)
“She confessed that she had taken the money”
state freely
“The teacher professed that he was not generous when it came to giving good grades”
receive into a religious order or congregation
take vows, as in religious order
“she professed herself as a nun”
Synonyms, antonyms and the broader and narrower relations for profess come from Princeton University’s WordNet. Full sources and licences.