Ardent, a.
Etymology: [OE. ardaunt, F. ardant, p. pr. of arder to burn, fr. L. ardere.]
1. Hot or burning; causing a sensation of burning; fiery; as, ardent spirits, that is, distilled liquors; an ardent fever.
2. Having the appearance or quality of fire; fierce; glowing; shining; as, ardent eyes. Dryden.
3. Warm, applied to the passions and affections; passionate; fervent; zealous; vehement; as, ardent love, feelings, zeal, hope, temper. An ardent and impetuous race. Macaulay.
Syn. -- Burning; hot; fiery; glowing; intense; fierce; vehement; eager; zealous; keen; fervid; fervent; passionate; affectionate.
Shades of meaning
Fernald has no entry of its own for ardent; he lists it under eager.
He lists it without comment; the entries above explain its neighbors.