σύνοιδα perf. with pres. sense, there being no pres. συνείδω 1st pl. ξύνισμεν 3rd pl. -ίσᾱσι imperat. ξύνισθι inf. -ειδέναι plup. with imperf. sense, συνῄδειν Attic -ῄδη dual -ῄστην pl. -ῇσμεν, -ῇστε, -ῇσαν Ionic 2nd pl. -ῃδέατε fut. συνείσομαι rarely συνειδήσω to share in knowledge, be cognisant of a thing, be privy to it, Lat. conscius esse, Hdt., Attic ἑαυτῷ συνειδέναι τι to be conscious of a thing, Ar., Plat., etc.:—with part., which may be in nom., ξ. ἐμαυτῷ οὐδʼ ὁτιοῦν σοφὸς ὤν Plat.; without the reflex. Pron. to be conscious that, ξύνοισθά γʼ εἰς ἔμʼ οὐκ εὔορκος ὤν Eur. in dat., ξ. ἐμαυτῷ οὐδὲν ἐπισταμένῳ I am conscious that I know nothing, Plat. in acc., ξύνοιδʼ Ὀρέστην σε ἐκπαγλουμένην I know well that thou admirest him, Aesch. absol. ξυνειδώς, an accomplice, ξ. τις Thuc.; also, ὁ ξ. τινι Thuc. neut. τὸ συνειδός συνείδησις, joint knowledge, consciousness, Dem.