Rĕc'ti-līn'e-al or Rĕc'ti-līn'e-ar, a.

a. [Lat. rectus, right, and linea, line; Fr. rectiligne, Sp. rectilineo, It. rettilineo.] Right-lined; consisting of a right line, or of right-lines; bounded by right lines; straight; as, a rectilinear figure or course; a rectilinear side or way.