GMAT Vocabulary Flash Cards @ englishpdf.com and englishteststore.com File 352 insomnia (n) Sleeplessness inspector (n) An official appointed to examine or oversee any matter of public interest or importance instance (n) A single occurrence or happening of a given kind instant (n) A very brief portion of time instantaneous (adj) Done without perceptible lapse of time instigate (v) To provoke instigator (n) One who incites to evil instill (v) To infuse