Adjective unimportant has 2 senses
- unimportant - not important; "a relatively unimportant feature of the system"; "the question seems unimportant"
Antonyms: important, of import, all-important, all important, crucial, essential, of the essence, alpha, arch, big, burning, cardinal, central, fundamental, key, primal, chief, main, primary, principal, consequential, eventful, Copernican, distinguished, eminent, great, grave, grievous, heavy, weighty, historic, in-chief, measurable, most-valuable, serious, strategic, useful, valuable, of value, beta
- insignificant, unimportant - not important or noteworthy
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