εἴδω

eídō. a primary verb; used only in certain past tenses, the others being borrowed from the equivalent ὀπτάνομαι and ὁράω; properly, to see (literally or figuratively); by implication, (in the perfect tense only) to know:--be aware, behold, X can (+ not tell), consider, (have) know(-ledge), look (on), perceive, see, be sure, tell, understand, wish, wot. Compare ὀπτάνομαι.