sincere
adj.adj. honest and real in what you say or feel. When you are sincere, you are not pretending or trying to trick anyone.
adj. characterised by genuine feelings or intentions; free from hypocrisy or deceit. Typically used to describe personal attributes, apologies, or expressions of emotion.
Please accept my sincere apologies for the mistake.
Her sincere interest in the local history impressed the residents during the interview.
The candidate's victory was attributed to a sincere communication style that resonated with voters tired of polished political rhetoric.
From Middle French sincere, from Latin sincerus (“genuine”), from Proto-Indo-European sem- (“together”) (whence English sam) + ḱer- (“grow”) (whence Latin Ceres, the goddess of harvest, etymon of cereal). Not from sine (“without”) + cera (“wax”), a folk etymology; see Wikipedia page.
Commonly modifies abstract nouns like 'apology', 'belief', 'effort', or 'interest'.