1. (

• coffer ,
• caisson ,
• lacunar

) an ornamental sunken panel in a ceiling or dome ;

2. (

• caisson ,

) a two-wheeled military vehicle carrying artillery ammunition ;

3. (

• caisson ,
• ammunition_chest

) a chest to hold ammunition ;

4. (

• caisson ,
• pneumatic_caisson ,
• cofferdam

) large watertight chamber used for construction under water ;