SINCERITY
seriousness, earnestness, serious-mindedness, sincerity
(noun) the trait of being serious; “a lack of solemnity is not necessarily a lack of seriousness”- Robert Rice
sincerity, unassumingness
(noun) a quality of naturalness and simplicity; “the simple sincerity of folk songs”
sincerity
(noun) the quality of being open and truthful; not deceitful or hypocritical; “his sincerity inspired belief”; “they demanded some proof of my sincerity”
earnestness, seriousness, sincerity
(noun) an earnest and sincere feeling
Source: WordNet® 3.1
Etymology
Noun
sincerity (countable and uncountable, plural sincerities)
The quality or state of being sincere; honesty of mind or intention; freedom from simulation, hypocrisy, disguise, or false pretense.
Synonyms
• honesty
• sincereness
Antonyms
• insincerity
Source: Wiktionary
Sin*cer"i*ty, n. Etym: [L. sinceritas: cf. F. sincérité.]
Definition: The quality or state of being sincere; honesty of mind or
intention; freedom from simulation, hypocrisy, disguise, or false
pretense; sincereness.
I protest, in the sincerity of love. Shak.
Sincerity is a duty no less plain than important. Knox.
Source: Webster’s Unabridged Dictionary 1913 Edition