Uttermost, a.
Etymology: [From Utter, a.; cf. Utmost, and Outermost.]
Extreme; utmost; being; in the farthest, greatest, or highest degree; as, the uttermost extent or end. "In this uttermost distress." Milton.
1 other Webster entry under this spelling
Uttermost, n.
The utmost; the highest or greatest degree; the farthest extent. Tennyson. Wherefore he is able also to save them to the uttermost that come unto God by him. Heb. vii. 25. He cannot have sufficient honor done unto him; but the uttermost we can do, we must. Hooker.
Shades of meaning
Fernald has no entry of its own for uttermost; he lists it under end.
He lists it without comment; the entries above explain its neighbors.