frederick ii has 2 distinct synonyms spread across 2 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. 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.
king of Prussia from 1740 to 1786; brought Prussia military prestige by winning the War of the Austrian Succession and the Seven Years' War (1712-1786)
the Holy Roman Emperor who led the Sixth Crusade and crowned himself king of Jerusalem (1194-1250)
Synonyms, antonyms and the broader and narrower relations for frederick ii come from Princeton University’s WordNet. Full sources and licences.