An instrument for injecting fluid into, or withdrawing fluid from, a body cavity, tissue or blood vessel. The basic design is of a calibrated barrel with a plunger at one end and a nozzle to which a hollow needle can be attached at the other end. Most syringes are disposable, plastic, presterilised and packed in sealed containers. Injections can be given under the skin, into muscle, into a vein or into the CEREBROSPINAL FLUID. Ear syringes are used to flush out wax from the auditory canal.