Shelf \Shelf\, n.; pl. Shelves. [OE. shelfe, schelfe, AS. scylfe; akin to G. schelfe, Icel. skj[=a]lf. In senses 2 & 3, perhaps a different word (cf. Shelve, v. i.).]

1. (Arch.) A flat tablet or ledge of any material set horizontally at a distance from the floor, to hold objects of use or ornament.

2. A sand bank in the sea, or a rock, or ledge of rocks, rendering the water shallow, and dangerous to ships.

On the tawny sands and shelves. --Milton.

On the secret shelves with fury cast. --Dryden.

3. (Mining) A stratum lying in a very even manner; a flat, projecting layer of rock.

4. (Naut.) A piece of timber running the whole length of a vessel inside the timberheads. --D. Kemp.

To lay on the shelf, to lay aside as unnecessary or useless; to dismiss; to discard.

Source: Webster's Revised Unabridged Dictionary (1913)