subsection

Short definition from Wiktionary

Noun

1. 1
   A defined part of a section.
2. 2
   A subpart of a legal document such as law.
3. 3
   An informal taxonomic category below section and above family.
4. 4
   A taxonomic rank below section and above species.

Verb

1. 1
   To insert subsections (into some text, etc.).