can I use definition lists just like unordered/ordered lists?
I mean insert DIVs any anything I want inside DT or DD?
<dl>
<dt>
...
</dt>
<dd>
...
</dd>
</dl>
Do any browsers, or search engines complain?
Updated answer based on comments:
This was originally answered in 2011 for HTML 4, but the answer is different for HTML5:
dt
Flow content, but with no header, footer, sectioning content, or heading content descendants.dd
Flow content.
Original answer:
DT
elements should contain inline content.
DD
elements should contain block-level content.
Definition lists vary only slightly from other types of lists in that list items consist of two parts: a term and a description. The term is given by the DT element and is restricted to inline content. The description is given with a DD element that contains block-level content.
Source: W3C
This question is also an interesting read: Why use definition lists (DL,DD,DT) tags for HTML forms instead of tables?