ideo·gram
1 : a picture or symbol used in a system of writing to represent a thing or an idea but not a particular word or phrase for it
especially : one that represents not the object pictured but some thing or idea that the object pictured is supposed to suggest
https://www.merriam-webster.com/dictionary/ideogram
Numbers are ideograms. They represent the idea of quantity or amount. Mathematical symbols are ideograms, too—‘+’ means added to, ‘-’ means subtracted from. Those are abstract ideas. The plus or minus sign doesn’t represent anything you can see or touch.
A red circle with a bar through it means ‘no’ or ‘not allowed.’ That’s an idea. If you put the red circle and bar across a picture of a cigarette or dog or a skateboard, you know those things aren’t allowed. The cigarette or dog or skateboard are pictograms. They represent something you can see or touch. The red circle and bar turn them into ideograms: the idea of something being forbidden.
Can you think of any ideograms? You see them everywhere. They’re especially useful to communicate without needing to speak a particular language. Anyone at an international airport can find someplace to eat, a gender-appropriate potty, the baggage claim or a taxi thanks to pictograms and ideograms. Ideograms on the road tell a driver when to slow down, merge with other traffic, or stop. Do you see any ideograms at home? At school? On your computer?
https://penandthepad.com/types-imagery-poetry-19888.html (scroll down)
Back to the beginning of The Western Civ User’s Guide to Reading & Writing.