Word Origin and History for tertiary Expand. adj. 1650s, of the third order, rank, degree, etc., from Latin tertiarius of or pertaining to a third, from tertius third, a third, from root of tres three (see three).
Water and Fluid retention in legs, also known as edema, is a medical condition caused by abnormal accumulation of water or fluids in the bodyâs tissues. Though excess water can be accumulated anywhere in the body, the most common areas are the ankles and legs.
Answers from Sheldon G. Sheps, M.D. Leg and foot swelling during air travel is common and typically harmless. The most likely culprit is inactivity during a flight. Sitting with your feet on the floor for a long period causes blood to pool in your leg veins. The position of your legs when you are seated also increases pressure in your leg veins. This contributes to foot swelling by causing fluid to leave the blood and move into the surrounding soft tissues.