断面

The term refers specifically to the surface that becomes visible after an object has been cut or sliced. It is used across various fields, from culinary arts (showing the layers of a cake) to geology and engineering (analyzing the internal structure of a material).

In a technical or academic context, it is frequently paired with the word 図 (zu), forming 断面図 (danmen-zu), which means a cross-sectional diagram or a blueprint showing the internal view of an object.

While in English "cross-section" can be used metaphorically to describe a representative sample of a group (e.g., "a cross-section of society"), in Japanese, 断面 is predominantly used for physical surfaces. For metaphorical "cross-sections," other terms like 切り取り (kiritori) or 縮図 (shukuzu) are more natural depending on the context.