caisson

noun

1. an ornamental sunken panel in a ceiling or dome

Similar word(s): coffer, lacunar

Definition categories: man–made, panel

2. a two-wheeled military vehicle carrying artillery ammunition

Definition categories: man–made

3. a chest to hold ammunition

Definition categories: man–made, chest

4. large watertight chamber used for construction under water

Similar word(s): cofferdam

Definition categories: man–made, chamber