Steadfast, a.
Etymology: [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.
Shades of meaning
Fernald has no entry of its own for steadfast; he lists it under permanent.
He lists it without comment; the entries above explain its neighbors.