UNWAVERING
firm, steadfast, steady, stiff, unbendable, unfaltering, unshakable, unwavering
(adjective) marked by firm determination or resolution; not shakable; “firm convictions”; “a firm mouth”; “steadfast resolve”; “a man of unbendable perseverence”; “unwavering loyalty”
level, unwavering
(adjective) not showing abrupt variations; “spoke in a level voice”; “she gave him a level look”- Louis Auchincloss
Source: WordNet® 3.1
Etymology
Adjective
unwavering (comparative more unwavering, superlative most unwavering)
Never doubted; always steady and on course
Synonyms: constant, resolute, staunch, steadfast
Source: Wiktionary