water has 10 distinct synonyms spread across 5 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.
binary compound that occurs at room temperature as a clear colorless odorless tasteless liquid; freezes into ice below 0 degrees centigrade and boils above 100 degrees centigrade; widely used as a solvent
once thought to be one of four elements composing the universe (Empedocles)
a facility that provides a source of water
“the town debated the purification of the water supply”
a liquid necessary for the life of most animals and plants
“he asked for a drink of water”
provide with water
“We watered the buffalo”
secrete or form water, as tears or saliva
“My mouth watered at the prospect of a good dinner”
fill with tears
“His eyes were watering”
Synonyms, antonyms and the broader and narrower relations for water come from Princeton University’s WordNet. Full sources and licences.