steadfast

adjectives

marked by firm determination or resolution; not shakable
"firm convictions"; "a firm mouth"; "steadfast resolve"; "a man of unbendable perseverence"; "unwavering loyalty"
firm, steadfast, steady, stiff, unbendable, unfaltering, unshakable, unwavering
is derived from
steadfastness
firm and dependable especially in loyalty
"a steadfast ally"; "a staunch defender of free speech"; "unswerving devotion"; "unswerving allegiance"
staunch, steadfast, unswerving
is derived from
steadfastness