Entry 1 sense Webster, 1913 Illusive /ĭlˌ-o͞os'-ĭv/ · Il·lu·sive · IPA /ɪˈluːsɪv/ 01 a. Deceiving by false show; deceitful; deceptive; false; illusory; unreal. 1. Deceiving by false show; deceitful; deceptive; false; illusory; unreal. “Truth from illusive falsehood to command.” — Thomson.