IELTS invisible Definition Unable to be seen; imperceptible to the eye. Example "The insect was nearly invisible against the leaf's surface." Sign in to save IELTS Quiz → ← inviolable inviting → Study tips featuring "invisible" Audit Your Own Writing to Find Gaps Boost Your IELTS Writing With Precise Vocabulary Related words IELTS sincere GRE abide SAT abnormal TOEFL aboard TOEFL abolition TOEFL abort IELTS abortion SAT abrupt SAT absence TOEFL absent GRE absolute TOEFL absolutely