n.

1. 插入；嵌入[U]
   The insertion of the needle under the skin made him wince.

   针刺入皮下使他畏缩起来。

2. 插入物[C][（+into）]
   an insertion into a text

   正文的插入材料

3. （服装上的）嵌饰，边饰[C]
4. （报纸等的）插入的广告[C]
5. 【解】肌肉等的附着处[C]

n.

1. the action of inserting.
2. something inserted, such as an addition to a text.
   ▸each appearance of an advertisement in a newspaper or periodical.
3. Anatomy  & Zoology  the manner or place of attachment of an organ or muscle.