Synonyms for Freelance (same or very similar meaning)
WordNet sense 1 (a writer or artist who sells services to different employers without a long-term contract with any of them):
independent, self-employed person
WordNet sense 2 (used of soldiers hired by a foreign army):
mercenary
WordNet sense 3 (marked by the reception of pay):
paid
WordNet sense 4 (working for yourself):
self-employed
From the ODE community, based on WordNet
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