pneu·mat·ic / n(y)oōˈmatik/ • adj. 1. containing or operated by air or gas under pressure. ∎  Zool. (chiefly of cavities in the bones of birds) containing air. ∎ inf. (of certain body parts, esp. a woman’s breasts) large, as if inflated: she’s the one with the pneumatic lips and breasts. ∎ inf. (of a woman) having large breasts: Lee and his pneumatic wife.2. of or relating to the spirit.• n. (usu. pneumatics) an item of pneumatic equipment.DERIVATIVES: pneu·mat·i·cal·ly / n(y)oōˈmadək(ə)lē/ adv.pneu·ma·tic·i·ty / ˌn(y)oōməˈtisədē/ n.

pneumatic Device powered by compressed air normally used to produce rotary or a reciprocating (back and forth) motion to speed up operations such as sawing, grinding, digging, hammering and riveting. The pneumatic drill used in roadworks has a reciprocating, pounding motion, turning at speeds of between 80 and 500 revolutions per minute.

pneumatic XVII. — F. pneumatique or L. pneumaticus — Gr. pneumatikós, f. pneûma, pneumat- wind, breath, spirit; see -IC.