Emily Dickinson Lexicon

ROOF, n. [Sax. rof, hrof; Gr. οροφη, οροφος, from ερεφω, to ψοωερ. Qu. Russ. krov, Slav. strop. See Ar. Class Rb, No. 12, and Syr. No. 40.]

1. The cover or upper part of a house or other building, consisting of rafters covered with boards, shingles or tiles, with a side or sides sloping from the ridge, for the purpose of carrying off the water that falls in rain or snow. In Asia, the roofs of houses are flat or horizontal. The same name, roof, is given to the sloping covers of huts, cabins and ricks; to the arches of ovens, furnaces, &c.
2. A vault; an arch; or the interior of a vault; as, the roof of heaven.
3. The vault of the mouth; the upper part of the mouth; the palate. If I do not remember thee, let my tongue cleave to the roof of my mouth. – Ps. cxxxvii.