n. [ Gr. &unr_;, fr. &unr_; to mark out by lines; dia` through + &unr_; to draw, write: cf. F. diagramme. See Graphic. ] 1. (Geom.) A figure or drawing made to illustrate a statement, or facilitate a demonstration; a plan. [ 1913 Webster ]
2. Any simple drawing made for mathematical or scientific purposes, or to assist a verbal explanation which refers to it; a mechanical drawing, as distinguished from an artistical one. [ 1913 Webster ]
Indicator diagram. (Steam Engine) See Indicator card, under indicator [ 1913 Webster ]