machine has 6 distinct synonyms spread across 3 of its 8 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.
any mechanical or electrical device that transmits or modifies energy to perform or assist in the performance of human tasks
Synonyms, antonyms and the broader and narrower relations for machine come from Princeton University’s WordNet. Full sources and licences.
an intricate organization that accomplishes its goals efficiently
“the war machine”
a device for overcoming resistance at one point by applying force at some other point
a group that controls the activities of a political party
“he was endorsed by the Democratic machine”
a motor vehicle with four wheels; usually propelled by an internal combustion engine
“he needs a car to get to work”