unnecessary UK /ʌnˈnɛs.ə.s(ə)ɹɪ/US /ʌnˈnɛs.əˌsɛɹ.i/ adjective2 •not needed, or more than a situation calls forThe automatic child-frightener made clowns unnecessary. •Done in addition to requirements; unrequired. formsmore unnecessary · most unnecessary