Definition of diagram in English:



  • 1A simplified drawing showing the appearance, structure, or workings of something; a schematic representation.

    ‘a diagram of the living room’
    • ‘The text is well illustrated with excellent diagrams, sketches and figures.’
    • ‘This diagram shows the complex structure of Saturn's magnetosphere.’
    • ‘Fig.14 shows schematic diagrams representing this type of situation.’
    • ‘Follow the manufacturer's wiring diagram to make the connection to your power supply.’
    • ‘The book is profusely illustrated, with diagrams showing clearly the techniques described.’
    • ‘Schematic diagrams of the probe and of the entire spectroscopy system are shown in Fig.1.’
    • ‘The data are summarized in the schematic diagram below.’
    • ‘In the following paragraphs I will use four simple diagrams to present the argument.’
    • ‘On the second point, I think the member has heard the explanation many times before: a graph or a diagram appeared in a document that was not authorised by the Prime Minister or me.’
    • ‘The system can be used to display schematic diagrams of the aircraft's principal sub-systems.’
    • ‘The diagrams illustrating the normal histology of the spleen are comprehensible and significantly clarify a fairly complicated system.’
    • ‘Line drawings and diagrams in the text figures are typically well designed and informative.’
    • ‘The text also includes many diagrams of molecular structures and points out the relevance and importance of the chemical structure to the pharmacological action.’
    • ‘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.’
    • ‘The first weeks of the course deal with electronic principles, electrical-current theory, and the skills needed to interpret equipment diagrams and schematics.’
    • ‘A diagram of the hillside structure is shown on Page 82.’
    • ‘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.’
    • ‘For every birdhouse, you'll find a photo, an exploded diagram of all sides, and simple instructions.’
    • ‘A summary flow diagram of patients enrolled in the study is depicted in Figure 1.’
    • ‘The dissertation is well organized with many fascinating diagrams, charts and figures.’
    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
    View synonyms
    1. 1.1Geometry A figure composed of lines that is used to illustrate a definition or statement or to aid in the proof of a proposition.
      • ‘Stefan handed some chalk to Spencer who began drawing various diagrams on the board.’
      • ‘Along with many line diagrams and equations, the problems and ‘mathematical meanderings’ strengthen concepts in each chapter.’
    2. 1.2British A graphical schedule for operating railway locomotives and rolling stock in order to provide a desired service.
      • ‘It was an ‘expo on wheels’, displaying the highlights of the railway network through charts, diagrams, photographs and working models.’
      • ‘Another 12 Class 317 electric trains and 14 more Class 319 units will ensure all diagrams can be run.’
      • ‘But a number of photographs feature interesting vehicles and are supplemented by coach diagrams, schedules and menus.’
      • ‘A navigational system pinpoints the train's position in relation to track diagrams.’
      • ‘To see a layout diagram of Amtrak's sleepers click here.’


  • 1 Represent (something) in graphic form.

    ‘the experiment is diagrammed on page fourteen’
    • ‘Unfortunately, this way of diagramming the results tends to lull us into thinking that all the evolutionary changes occurred at those nodes, and none along the branches.’
    • ‘Fig 1A.2 diagrams the G matrix and PCs associated with two populations, both of which have the modules diagrammed in Fig 1A.1.’
    • ‘By diagramming actual people in actual relationships, we are introducing both mechanical and conceptual problems.’
    • ‘A genetic map showing the 16 chromosomes of yeast is diagrammed.’
    • ‘There assistants corrected the proportions of the initial sketches in carefully diagrammed drawings and clay models so they conformed to the perfect mathematical ratios.’
    • ‘In the heat of the action, the coach eagerly diagrams a play and talks his players through it.’
    • ‘He diagrammed it on a piece of paper, then shared it with Nick Scheele and Jim Padilla.’
    • ‘Although only three lineages are diagrammed, in reality an average of >100 lineages were propagated for each genotype.’
    • ‘I might instead attempt to diagram its structure, insofar as I am able to apprehend it.’
    • ‘It is an attempt to diagram the allies, enemies, cousins, straw men, party followers, puppets, and courtiers and their relationships.’
    • ‘All we see are coaches discussing certain planned options, not actually diagramming the procedures for us.’
    • ‘The screening method is diagrammed in Fig 1A and represents a modification of the crossing design of COYNE et al. 1998.’
    • ‘This simplified figure fails to show the interrelationship between those two processes and unrealistically diagrams the recombination as reciprocal.’
    • ‘He also diagrams the road graph that gives rise to this state of affairs.’
    • ‘In terms of the competition of routes, he diagrammed cases where more roundabout routes may be economically defensible.’
    • ‘He assembled all the helicopter crews and briefed them on the mission, diagramming the procedure on butcher-block paper.’
    • ‘Take note of all important aspects of the collision and then if possible diagram the exact position of the vehicles before and after the accident.’
    • ‘Our experimental set-up is diagrammed in Figure 2A.’
    • ‘The Kensico Cemetery burial card diagrams the wedge-shaped plot, 5 feet by 8 by 40.’
    • ‘This coordinated ECR model is diagrammed in Fig 5.’
    1. 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.