independent has 11 distinct synonyms spread across 4 of its 6 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 dependent.
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.
free from external control and constraint
“an independent mind”
(of political bodies) not controlled by outside forces
“an autonomous judiciary”
a neutral or uncommitted person (especially in politics)
a writer or artist who sells services to different employers without a long-term contract with any of them
1 of the 6 recorded senses carries no synonym, antonym or related term, so it is not shown above. Every sense, with its definition and examples, is on the full entry for independent.
Synonyms, antonyms and the broader and narrower relations for independent come from Princeton University’s WordNet. Full sources and licences.