WordNet records no synonym and no antonym for bishop. It is the only member of each of its synsets, which is common for technical, taxonomic and single-sense vocabulary — there is no other English word that means the same thing. The broader and narrower terms below are the useful relations in that case.
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 senior member of the Christian clergy having spiritual and administrative authority; appointed in Christian churches to oversee priests or ministers; considered in some churches to be successors of the twelve Apostles of Christ
port wine mulled with oranges and cloves
(chess) a piece that can be moved diagonally over unoccupied squares of the same color
Synonyms, antonyms and the broader and narrower relations for bishop come from Princeton University’s WordNet. Full sources and licences.