Possible Definitions:
1. Coffer (n.) A casket, chest, or trunk; especially, one used for keeping money or other valuables.
2. Coffer (n.) Fig.: Treasure or funds; -- usually in the plural.
3. Coffer (n.) A panel deeply recessed in the ceiling of a vault, dome, or portico; a caisson.
4. Coffer (n.) A trench dug in the bottom of a dry moat, and extending across it, to enable the besieged to defend it by a raking fire.
5. Coffer (n.) The chamber of a canal lock; also, a caisson or a cofferdam.
6. Coffer (v. t.) To put into a coffer.
7. Coffer (v. t.) To secure from leaking, as a shaft, by ramming clay behind the masonry or timbering.
8. Coffer (v. t.) To form with or in a coffer or coffers; to furnish with a coffer or coffers.
