significant Antonyms

insignificant nonsignificant slight negligible trivial undistinctive unknown unmeaning unsignificant useless valueless worthless unimportant trifling tiny puny purposeless secondary second-rate slink small subordinate substract superficial supplementary irrelevant unnecessary small-time noncritical ignorable penlight second string subatomic sub-par subpar unpersuasive low value derisorily undistinguished incidental atonalism little league ankle-deep lightweight footling piffling meaningless nonmeaningful Mickey Mouse less important