1) Centesis 2) Medical treatment 
Arthrocentesis (arthros, a joint + kentēsis, puncture) is the clinical procedure of using a syringe to collect synovial fluid from a joint capsule. It is also known as joint aspiration. Arthrocentesis is used in the diagnosis of gout, arthritis, and synovial infections such as septic arthritis. == See also == ...
<obstetrics, procedure> A procedure where by a needle in introduced into a joint space for the purpose of removing joint fluid for diagnostic purposes. This procedure can also be therapeutic if an anaesthetic or corticosteroid medication is injected into the joint during the procedure. ... (27 Sep 1997) ... 
(ahr″thro-sen-te´sis) surgical puncture of a joint cavity for aspiration of fluid.
Type: Term Pronunciation: ar′thrō-sen-tē′sis Definitions: 1. Aspiration of fluid from a joint performed by needle puncture.
Arthrocentesis: Joint aspiration, a procedure whereby a sterile needle and syringe are used to drain fluid from a joint. This is usually done as an office procedure or at the bedside in the hospital. For an arthrocentesis, the skin over the joint is sterilized with a liquid. Local anesthetic is applied to the area of the joint either by injection o...
[n] - removal of fluid from a joint by centesis
noun removal of fluid from a joint by centesis
Incision into a joint; puncture with a needle