(1):
(a.) Fitted to contain air; Having cavities filled with air; as, pneumatic cells; pneumatic bones.
(2):
(a.) Adapted for containing compressed air; inflated with air; as, a pneumatic cushion; a pneumatic tire, a tire formed of an annular tube of flexible fabric, as India rubber, suitable for being inflated with air.
(3):
(a.) Consisting of, or resembling, air; having the properties of an elastic fluid; gaseous; opposed to dense or solid.
(4):
(a.) Of or pertaining to air, or to elastic fluids or their properties; pertaining to pneumatics; as, pneumatic experiments.
(5):
(a.) Moved or worked by pressure or flow of air; as, a pneumatic instrument; a pneumatic engine.