constantinople has 7 distinct synonyms spread across 5 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 largest city and former capital of Turkey; rebuilt on the site of ancient Byzantium by Constantine I in the fourth century; renamed Constantinople by Constantine who made it the capital of the Byzantine Empire; now the seat of the Eastern Orthodox Church
the council in 869 that condemned Photius who had become the patriarch of Constantinople without approval from the Vatican, thereby precipitating the schism between the eastern and western churches
the sixth ecumenical council in 680-681 which condemned Monothelitism by defining two wills in Christ, divine and human
the fifth ecumenical council in 553 which held Origen's writings to be heretic
the second ecumenical council in 381 which added wording about the Holy Spirit to the Nicene Creed
Synonyms, antonyms and the broader and narrower relations for constantinople come from Princeton University’s WordNet. Full sources and licences.