tip truck has 5 distinct synonyms spread across 1 of its 1 sense. 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.
truck whose contents can be emptied without handling; the front end of the platform can be pneumatically raised so that the load is discharged by gravity
Synonyms, antonyms and the broader and narrower relations for tip truck come from Princeton University’s WordNet. Full sources and licences.