noun
schematic diagram
A simplified drawing that shows the structure or principle of something, often used in science, engineering, and instruction manuals.
この模式図は回路の動作原理を説明している。
This schematic diagram explains the operating principle of the circuit.
教科書の模式図を見れば、細胞の構造がよくわかる。
If you look at the schematic diagram in the textbook, you can clearly understand the structure of the cell.
略図 is a rough sketch or simplified map, often hand-drawn, whereas 模式図 is a more formal, often technical schematic.
Compound of 模式 (もしき, 'model' or 'pattern') and 図 (ず, 'diagram'). The term is a modern technical coinage.