A far more sober artist than Hugo, he was also a far profounder thinker, and a sincerer man.
I am indeed—but no man, as to you, Madam, ever had a sincerer heart.
To Lucilius he pays also the sincerer tribute of frequent imitation.
There is a sincerer strain in the book than in some of its predecessors.
It was fortunate for letters that they had sincerer friends in London than Wolsey.
He had the "gift of gab," yet he was no humbug; indeed, a sincerer parson does not exist.
In a happy hour the collector with his treasury and the teacher, pining for some fresher and sincerer melodies, met together.
There are no sincerer words in his letters than those which relate to Mrs. Pope.
Also deep down in his mind he had a sincerer and quite secret reason for reticence, whereof more in its proper place.
But as her friend he could have wished her a freer and sincerer inspiration.
1530s, "pure, unmixed," from Middle French sincere (16c.), from Latin sincerus, of things, "whole, clean, pure, uninjured, unmixed," figuratively "sound, genuine, pure, true, candid, truthful," of uncertain origin. Ground sense seems to be "that which is not falsified." Meaning "free from pretense or falsehood" in English is from 1530s.
There has been a temptation to see the first element as Latin sine "without." But there is no etymological justification for the common story that the word means "without wax" (*sin cerae), which is dismissed out of hand by OED and others, and the stories invented to justify that folk etymology are even less plausible. Watkins has it as originally "of one growth" (i.e. "not hybrid, unmixed"), from PIE *sm-ke-ro-, from *sem- "one" (see same) + root of crescere "to grow" (see crescent).