north has 10 distinct synonyms spread across 5 of its 9 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 south.
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 region of the United States lying to the north of the Mason-Dixon line
the United States (especially the northern states during the American Civil War)
“he has visited every state in the Union”
the cardinal compass point that is at 0 or 360 degrees
a location in the northern part of a country, region, or city
the direction corresponding to the northward cardinal compass point
the direction in which a compass needle points
British statesman under George III whose policies led to rebellion in the American colonies (1732-1792)
situated in or facing or moving toward or coming from the north
“artists like north light”
Synonyms, antonyms and the broader and narrower relations for north come from Princeton University’s WordNet. Full sources and licences.