Colossal, a.
Etymology: [Cf. F. cossal, L. colosseus. See Colossus.]
1. Of enormous size; gigantic; huge; as, a colossal statue. "A colossal stride." Motley.
2. (Sculpture & Painting)
Of a size larger than heroic. See Heroic.
Shades of meaning
Fernald has no entry of its own for colossal; he lists it under large.
He lists it without comment; the entries above explain its neighbors.