Meaning of DIAGRAM in English
[ 'dʌɪəgram ]
1》 a simplified drawing showing the appearance or structure of something.
2》 Brit. a graphical schedule for operating railway stock to provide a desired service.
■ verb ( ~s , ~ming , ~med ; US ~s , ~ing , ~ed )
1》 represent in graphic form.
2》 Brit. schedule the operations of (a locomotive or train) according to a ~.
~matic -grə'matɪk adjective
C17: from L. ~ma , from Gk, from diagraphein 'mark out by lines'.
Concise Oxford English vocab. Сжатый оксфордский словарь английского языка. 2004