element has 5 distinct synonyms spread across 3 of its 7 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.
an abstract part of something
“jealousy was a component of his character”
Synonyms, antonyms and the broader and narrower relations for element come from Princeton University’s WordNet. Full sources and licences.
an artifact that is one of the individual parts of which a composite entity is made up; especially a part that can be separated from or attached to a system
“spare components for cars”
any of the more than 100 known substances (of which 92 occur naturally) that cannot be separated into simpler substances and that singly or in combination constitute all matter
the most favorable environment for a plant or animal
“water is the element of fishes”
the situation in which you are happiest and most effective
“in your element”
a straight line that generates a cylinder or cone