Shelf

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