contain · appearance

1. Origins, structure, and basic meaning

• Structure: 容 conveys containment or appearance; its on-reading is よう.
• Basic usage: 内容（ないよう） means content, while 容器（ようき） means a container for objects or liquids.

2. Common pitfalls and similar expressions

• Communicated content and a physical container
  • 手紙の内容 means the contents of a letter, and 講座の内容 means what a course covers. In these uses, 内容 does not refer to a physical vessel.
  • 容器 is a vessel used for transferring leftover food or holding liquid without leaking. Although 容 occupies different positions in the two words, it is read よう in both.