Top Definition
HDML stands for Herp-Derp Markup Language. Broken or incorrectly implemented HTML that ends up being displayed as garbled text on the page, such as the following:

Show the one you love how you <i>really</i> feel this Christmas!
The frequent occurrence of HDML in the stranger's email body led Randolph Carter to suspect a phishing scheme.
by hypomnesis March 09, 2011

Free Daily Email

Type your email address below to get our free Urban Word of the Day every morning!

Emails are sent from daily@urbandictionary.com. We'll never spam you.

×