I. di ‧ a ‧ gram 1 S3 /ˈdaɪəɡræm/ BrE AmE noun [countable]
[ Date: 1600-1700 ; Language: Greek ; Origin: diagramma , from diagraphein 'to mark out with lines' ]
a simple drawing or plan that shows exactly where something is, what something looks like, or how something works
diagram of
a diagram of the heating system
—diagrammatic /ˌdaɪəɡrəˈmætɪk◂/ adjective
—diagrammatically /-kli/ adverb
II. diagram 2 BrE AmE verb ( past tense and past participle diagrammed , present participle diagramming ) [transitive]
to show or represent something in a diagram