diagram

Etymology

From French diagramme, from Italian diagramma, from Ancient Greek διάγραμμα (diágramma).

noun

1. A plan, drawing, sketch or outline to show how something works, or show the relationships between the parts of a whole.
   Drawings and pictures are more than mere ornaments in scientific discourse. Blackboard sketches, geological maps, diagrams of molecular structure, astronomical photographs, MRI images, the many varieties of statistical charts and graphs: These pictorial devices are indispensable tools for presenting evidence, for explaining a theory, for telling a story. 2012-03, Brian Hayes, “Pixels or Perish”, in American Scientist, volume 100, number 2, archived from the original on 2013-02-19, page 106
   Electrical diagrams show device interconnections.
2. A graph or chart.
   A common way to represent change in state over time is via a timing diagram. 1999, Bruce Powel Douglass, Doing Hard Time: Developing Real-time Systems with UML, Objects, Frameworks, and Patterns, page 520
   This particular diagram represents a dinosaur in the distant past and a person who is born in AD 2000. These objects stretch out horizontally in the graph because they last over time in reality, and time is the horizontal axis on the graph 2010, Susan Schneider, Science Fiction and Philosophy
   Various terms for this type of graph seem to be used interchangeably: 'scatter diagram', 'scatter graph' and 'scatter plot'. 2013, Caroline Rickard, Essential Primary Mathematics, page 215
   This powerful visual tool, known as the sawtooth diagram, is used to analyze inventory behavior over time. 2016, Stephen Cimorelli, Kanban for the Supply Chain, page 29
   We can then chart them over time and it results in that kind of a diagram. 2017, Sherman Wilcox, Ten Lectures on Cognitive Linguistics and the Unification of Spoken and Signed Languages, page 177
3. (category theory) A functor from an index category to another category. The objects and morphisms of the index category need not have any internal substance, but rather merely outline the connective structure of at least some part of the diagram's codomain. If the index category is J and the codomain is C, then the diagram is said to be "of type J in C".

verb

1. (transitive) To represent or indicate something using a diagram.
2. (UK) To schedule the operations of a locomotive or train according to a diagram.
   The timing and diagramming staff, too, were on duty for up to 21 hours devising 80 engine, 60 guards' and 25 carriage working diagrams. 1961 March, “Talking of trains”, in Trains Illustrated, page 131