ˈair-ˌchamber
[air- 7.]
1. a. Any chamber or cavity filled with air in an animal or plant, esp. those in a ‘chambered-shell.’
| 1847 Ansted Anc. World iii. 43 In the Nautilus..we find a large, powerful, and complicated shell, composed of a number of separate compartments or air-chambers. 1855 Owen Vertebr. i. ii. (L.) These air-chambers between the outer table and the immediate covering of the brain. |
b. A chamber filled with air in a boat, airship, etc., to provide or assist buoyancy.
| 1881 W. D. Hay 300 Years Hence vii. 133 In the upper part [of the boat] was the entrance and air-chamber. 1882 Encycl. Brit. XIV. 570/2 The buoyancy of the institution's lifeboat..is secured chiefly by means of a watertight deck..and two large air-chambers, one in the bow, the other in the stern. 1908 H. G. Wells War in Air viii. §1 The airship was remarkably simple to construct: given the air-chamber material, the engines, [etc.]..it was really not more complicated..than an ordinary wooden boat had been..before. |
2. In a pump or other hydraulic machine, a receptacle containing air, the elasticity of which, when condensed, maintains a constant pressure upon the water; an air-vessel.
| 1873 Atkinson tr. Ganot's Physics §206 The fire engine is a force pump in which a steady jet is obtained by the aid of an air-chamber. |