Lĭn'e-ar, a.

a. [Lat. linearis, linearius, from linea, line, q. v.; Fr. linéaire, It. lineare, lineario.] 1. Pertaining to a line; consisting of lines; in a straight direction. 2. (Bot.) Like a line; slender; of the same breadth throughout, except at the extremities; as, a linear leaf.

Linear equation (Math.), an equation of the first degree between two variables;—so called because every such equation may be considered as representing a right line.—Linear numbers (Math.), such numbers as have relation to length only: such is a number which represents one side of a plane figure. If the plane figure is a square, the linear figure is called a root.—Linear perspective. See PERSPECTIVE.—Linear problem, a problem which may be solved geometrically by the use of right lines alone.