STEADFAST
steadfast, staunch, unswerving
(adjective) firm and dependable especially in loyalty; “a steadfast ally”; “a staunch defender of free speech”; “unswerving devotion”; “unswerving allegiance”
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”
Source: WordNet® 3.1
Etymology
Adjective
steadfast (comparative steadfaster or more steadfast, superlative steadfastest or most steadfast)
Fixed or unchanging; steady.
Firmly loyal or constant; unswerving.
Source: Wiktionary
Stead"fast, a. Etym: [Stead + fast, that is, fast in place.] Etym:
[Written also stedfast.]
1. Firmly fixed or established; fast fixed; firm. "This steadfast
globe of earth." Spenser.
2. Not fickle or wavering; constant; firm; resolute; unswerving;
steady. "Steadfast eye." Shak.
Abide steadfast unto him [thy neighbor] in the time of his trouble.
Ecclus. xxii. 23.
Whom resist steadfast in the faith. 1 Pet. v. 9.
Source: Webster’s Unabridged Dictionary 1913 Edition