Diagram (noun)

1. A simple drawing showing the form, structure, or arrangement of something, typically demonstrating relationships between things.
2. A graphical representation of a mathematical or scientific concept or problem.
3. A flowchart or flow diagram showing the sequence of actions, decisions, or steps in a process or system.

Origin:

Late 16th century: from french diagrame, from greek diagraphein 'mark out by lines', from dia- 'across' + graphein 'write'. the verb is from early 19th century.

Examples:

1. The architect showed us a diagram of the proposed building.
2. The teacher drew a diagram of the human eye on the blackboard.
3. The scientist used a diagram to explain the theory to the students.
4. The engineer created a diagram to show how the new system would work.
5. The consultant presented a diagram outlining the steps in the project.