synthesis has 3 distinct synonyms spread across 2 of its 3 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. Its one recorded opposite is analysis.
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.
the process of producing a chemical compound (usually by the union of simpler chemical compounds)
the combination of ideas into a complex whole
Synonyms, antonyms and the broader and narrower relations for synthesis come from Princeton University’s WordNet. Full sources and licences.
reasoning from the general to the particular (or from cause to effect)