Shelf

Part of speech: noun (n.)

1. 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. A stratum lying in a very even manner; a flat, projecting layer of rock.

4. 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.