What does XD stand for?

What does XD mean?

XD	Ex-Dividend Business » Stock Exchange
XD	Cross-Dresser Internet » Chat
XD	laughing face Internet » Emoticons
XD	Ximian Desktop Computing » Software
XD	XML Draw Computing » Software
XD	X- Dimensional Academic & Science » Mathematics
XD	Cross- Dated Governmental » US Government
XD	Cross- Dated Academic & Science » Botany
XD	eXtra Duty Governmental » Military
XD	eXtra Damage Community » Sports
XD	eXtra Dry Business » Products
XD	Xtreme Digital Business » Products
XD	Dead Fish Internet » Emoticons