Definition of diagram in English:

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Pronunciation: /ˈdʌɪəɡram/


1A simplified drawing showing the appearance, structure, or workings of something; a schematic representation: a diagram of the living room
More example sentences
  • They are packed with detail but it doesn't seem overwhelming because the pages are broken up with masses of superb colour photographs, maps, street-by-street diagrams and drawings.
  • Apart from the run-of-the-mill stuff like e-mail and word processing, he is teaching himself to use the computer to draw schematic diagrams.
  • The data are summarized in the schematic diagram below.
drawing, line drawing, illustration, picture, artist's impression;
schematic representation, representation, scale drawing, technical drawing, plan, figure, sketch, draft, outline, delineation, exploded view, cutaway, layout;
Computing  graphic
rare schema
1.1 Geometry A figure composed of lines that is used to illustrate a definition or statement or to aid in the proof of a proposition.
Example sentences
  • Along with many line diagrams and equations, the problems and ‘mathematical meanderings’ strengthen concepts in each chapter.
  • Stefan handed some chalk to Spencer who began drawing various diagrams on the board.
1.2British A graphical schedule for operating railway locomotives and rolling stock in order to provide a desired service.
Example sentences
  • But a number of photographs feature interesting vehicles and are supplemented by coach diagrams, schedules and menus.
  • Another 12 Class 317 electric trains and 14 more Class 319 units will ensure all diagrams can be run.
  • A navigational system pinpoints the train's position in relation to track diagrams.

verb (diagrams, diagramming, diagrammed; US diagrams, diagraming, diagramed)

[with object]
1Represent (something) in graphic form: the experiment is diagrammed on page fourteen
More example sentences
  • The screening method is diagrammed in Fig 1A and represents a modification of the crossing design of COYNE et al. 1998.
  • The Kensico Cemetery burial card diagrams the wedge-shaped plot, 5 feet by 8 by 40.
  • By diagramming actual people in actual relationships, we are introducing both mechanical and conceptual problems.
1.1British Schedule the operations of (a locomotive or train) according to a diagram.


Early 17th century: from Latin diagramma, from Greek, from diagraphein 'mark out by lines', from dia 'through' + graphein 'write'.

  • graft from Late Middle English:

    A graft is a shoot from one plant fixed into a slit made in another to form a new growth. Originally spelled graff, it derives from Greek graphion ‘stylus, pointed writing implement’, from graphein ‘to write’, source of the graphite (late 18th century) in your pencil, graphic art (mid 17th century), and diagram (early 17th century). The tapered tip of the shoot was thought to resemble a stylus. The other graft (mid 19th century), ‘hard work’, may be related to the phrase spade's graft ‘the amount of earth that one stroke of a spade will move’, based on Old Norse groftr ‘digging’.

For editors and proofreaders

Line breaks: dia|gram

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