adjective
1.
Synonyms: sure 2, abiding, enduring, never-failing, steadfast, steady, unfaltering, unqualified, unquestioning, unwavering
2.
Synonyms: sincere 1, heartfelt, hearty, unfeigned, whole-souled
Related Word: ardent, fervent, impassioned, passionate; earnest, serious; authentic, bona fide, genuine