pattern has 15 distinct synonyms spread across 8 of its 10 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.
a customary way of operation or behavior
“it is their practice to give annual raises”
something regarded as a normative example
“the convention of not naming the main character”
a model considered worthy of imitation
“the American constitution has provided a pattern for many republics”
the path that is prescribed for an airplane that is preparing to land at an airport
“the traffic patterns around O'Hare are very crowded”
graphical representation (in polar or Cartesian coordinates) of the spatial distribution of radiation from an antenna as a function of angle
form a pattern
“These sentences pattern like the ones we studied before”
Synonyms, antonyms and the broader and narrower relations for pattern come from Princeton University’s WordNet. Full sources and licences.