Noah Webster's Dictionary (n.) The quality of being insincere; want of sincerity, or of being in reality what one appears to be; dissimulation; hypocritical; deceitfulness; hollowness; untrustworthiness; as, the insincerity of a professed friend; the insincerity of professions of regard.

Multi-Version Concordance Insincerity (5 Occurrences) Matthew 23:28 The same is true of you: outwardly you seem to the human eye to be good and honest men, but, within, you are full of insincerity and disregard of God's Law. (WEY) Galatians 2:13 And the rest of the Jews joined him in his hypocrisy; so that even Barnabas was carried away with their hypocrisy. (See RSV) Titus 2:7 and above all make your own life a pattern of right conduct, having in your teaching no taint of insincerity, but a serious tone, (WEY) James 3:17 The wisdom from above is first of all pure, then peaceful, courteous, not self-willed, full of compassion and kind actions, free from favouritism and from all insincerity. (WEY RSV) 1 Peter 2:1 Rid yourselves therefore of all ill-will and all deceitfulness, of insincerity and envy, and of all evil speaking. (WEY RSV)