Synonyms for Independent (same or very similar meaning)
WordNet sense 1 (a neutral or uncommitted person (especially in politics)):
mugwump, fencesitter
WordNet sense 2 (a writer or artist who sells services to different employers without a long-term contract with any of them):
freelance, self-employed person
WordNet sense 3 ((of political bodies) not controlled by outside forces):
self-governing, sovereign
WordNet sense 4 (able to act at will; not hampered; not under compulsion or restraint):
free
WordNet sense 5 ((of a clause) capable of standing syntactically alone as a complete sentence):
main
WordNet sense 6 (not contingent; not determined or influenced by someone or something else):
unconditional
WordNet sense 7 (existing as an independent entity):
autonomous
WordNet sense 8 ((of persons) free from external control and constraint in e.g. action and judgment):
self-reliant, self-directed
WordNet sense 9 (perfect or complete or pure):
absolute
From the ODE community, based on WordNet
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