insincerea.[L. insincerus. See In- not, and Sincere.]()1. Not being in truth what one appears to be; not sincere; dissembling; hypocritical; disingenuous; deceitful; false; -- said of persons; also of speech, thought; etc.; as, insincere declarations.()2. Disappointing; imperfect; unsound.()To render sleep's soft blessings insincere. (Pope.)()