Di″a‐gram (?), n. [Gr. �, fr. � to mark out by lines; διά through + � 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.
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.
Indicator diagram. (Steam Engine) See Indicator card, under indicator