(n.) The margin, edge, verge, or border of a surface; especially (when the thing spoken of is somewhat oblong in shape), one of the longer edges as distinguished from the shorter edges, called ends; a bounding line of a geometrical figure; as, the side of a field, of a square or triangle, of a river, of a road, etc.
SIDE
Meaning of SIDE in English
Webster's English dictionary. Английский словарь Webster. 2012