Diaphanous, a.
Etymology: [Gr. diaphane. See Phantom, and cf. Diaphane, Diaphanic.]
Allowing light to pass through, as porcelain; translucent or transparent; pellucid; clear. Another cloud in the region of them, light enough to be fantastic and diaphanous. Landor.
Shades of meaning
Fernald has no entry of its own for diaphanous; he lists it under clear.
He lists it without comment; the entries above explain its neighbors.