dependent has 9 distinct synonyms spread across 6 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. Its one recorded opposite is independent.
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.
relying on or requiring a person or thing for support, supply, or what is needed
“dependent children”
(of a clause) unable to stand alone syntactically as a complete sentence
“a subordinate (or dependent) clause functions as a noun or adjective or adverb within a sentence”
addicted to a drug
Synonyms, antonyms and the broader and narrower relations for dependent come from Princeton University’s WordNet. Full sources and licences.