Antonyms of adj unimportant

2 senses of unimportant

Sense 1
unimportant (vs. important) -- (not important; "a relatively unimportant feature of the system"; "the question seems unimportant")

important (vs. unimportant), of import -- (of great significance or value; "important people"; "the important questions of the day")
        => all-important (prenominal), all important (predicate), crucial, essential, of the essence (predicate) -- (of the greatest importance; "the all-important subject of disarmament"; "crucial information"; "in chess cool nerves are of the essence")
        => alpha -- (first in order of importance; "the alpha male in the group of chimpanzees"; "the alpha star in a constellation is the brightest or main star")
        => beta -- (second in order of importance; "the candidate, considered a beta male, was perceived to be unable to lead his party to victory")
        => big -- (significant; "graduation was a big day in his life")
        => burning (prenominal) -- (of immediate import; "burning issues of the day")
        => cardinal, central, fundamental, key, primal -- (serving as an essential component; "a cardinal rule"; "the central cause of the problem"; "an example that was fundamental to the argument"; "computers are fundamental to modern industrial structure")
        => chief (prenominal), main (prenominal), primary (prenominal), principal (prenominal), master (prenominal) -- (most important element; "the chief aim of living"; "the main doors were of solid glass"; "the principal rivers of America"; "the principal example"; "policemen were primary targets"; "the master bedroom"; "a master switch")
        => consequential, eventful -- (having important issues or results; "the year's only really consequential legislation"; "an eventful decision")
        => Copernican -- (of radical or major importance; "a Copernican revolution in modern art")
        => distinguished -- ((used of persons) standing above others in character or attainment or reputation; "our distinguished professor")
        => grand -- (the most important and magnificent in adornment; "grand ballroom"; "grand staircase")
        => grave, grievous, heavy, weighty -- (of great gravity or crucial import; requiring serious thought; "grave responsibilities"; "faced a grave decision in a time of crisis"; "a grievous fault"; "heavy matters of state"; "the weighty matters to be discussed at the peace conference")
        => great, outstanding -- (of major significance or importance; "a great work of art"; "Einstein was one of the outstanding figures of the 20th centurey")
        => historic -- (important in history; "the historic first voyage to outer space")
        => in-chief (postnominal) -- (indicating the head of a staff; "editor-in-chief")
        => measurable -- (of distinguished importance; "a measurable figure in literature")
        => most-valuable -- (designating the player judged to be the most important to the sport; "the most-valuable player award")
        => serious -- (of great consequence; "marriage is a serious matter")
        => strategic -- (highly important to or an integral part of a strategy or plan of action especially in war; "a strategic chess move"; "strategic withdrawal"; "strategic bombing missions")

Sense 2
insignificant (vs. significant), unimportant -- (devoid of importance, meaning, or force)


Similarity of adj unimportant

2 senses of unimportant

Sense 1
unimportant (vs. important) -- (not important; "a relatively unimportant feature of the system"; "the question seems unimportant")
       => inconsequent, inconsequential -- (lacking worth or importance; "his work seems trivial and inconsequential"; "the quite inconsequent fellow was managed like a puppet")
       => immaterial, indifferent -- ((often followed by `to') lacking importance; not mattering one way or the other; "whether you choose to do it or not is a matter that is quite immaterial (or indifferent)"; "what others think is altogether indifferent to him")
       => fiddling, footling, lilliputian, little, niggling, piddling, piffling, petty, picayune, trivial -- ((informal) small and of little importance; "a fiddling sum of money"; "a footling gesture"; "our worries are lilliputian compared with those of countries that are at war"; "a little (or small) matter"; "a dispute over niggling details"; "limited to petty enterprises"; "piffling efforts"; "giving a police officer a free meal may be against the law, but it seems to be a picayune infraction")
       => lightweight -- (having no importance or influence; "a lightweight intellect")
       => nickel-and-dime, small-time -- (of minor importance; "a nickel-and-dime operation run out of a single rented room"; "a small-time actor")
       => potty -- ((British informal) trivial; "potty little details")
          Also See-> meaningless#1, nonmeaningful#1; inessential#1, unessential#1; insignificant#4, unimportant#2

Sense 2
insignificant (vs. significant), unimportant -- (devoid of importance, meaning, or force)
       => hole-and-corner, hole-in-corner -- (relating to the peripheral and unimportant aspects of life; "a hole-and-corner life in some obscure community"- H.G.Wells)
       => flimsy, fragile, slight, tenuous, thin -- (lacking substance or significance; "slight evidence"; "a tenuous argument"; "a thin plot"; a fragile claim to fame")
       => inappreciable -- (too small to make a significant difference; "inappreciable fluctuations in temperature")
       => light -- (having little importance; "losing his job was no light matter")
       => superficial, trivial -- (of little substance or significance; "a few superficial editorial changes"; "only trivial objections")
          Also See-> meaningless#1, nonmeaningful#1; unimportant#1