<DT>

Usage Recommendation
use it if you use <DL ...>

<DT> is used in conjunction with <DL ...> and <DD> to create definition lists. <DT> is usually used as the first part of a <DT>/<DD> combination. So, for example, this code creates three pairs of terms and definitions for the terms.

this code	produces this
<DL> <DT>flame <DD>an ugly argument in a newsgroup <DT>spam <DD>annoying unrequested email <DT>troll <DD>someone who start flames by posting stupid things </DL>	flame an ugly argument in a newsgroup spam annoying unrequested email troll someone who start flames by posting stupid things

<DT> is a container, so you can put a </DT> at the end of the term. However, the end tag is optional and is rarely used.