INSINCERE
insincere
(adjective) lacking sincerity; “a charming but thoroughly insincere woman”; “their praise was extravagant and insincere”
Source: WordNet® 3.1
Etymology
Adjective
insincere (comparative more insincere, superlative most insincere)
Not genuinely meaning what has been expressed; not sincere; artificial.
Antonyms
• sincere
Source: Wiktionary
In`sin*cere", a. Etym: [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. [Obs.]
To render sleep's soft blessings insincere. Pope.
Syn.
– Dissembling; hollow; hypocritical; deceptive deceitful; false;
disingenuous; untrustworthy.
Source: Webster’s Unabridged Dictionary 1913 Edition