look up any word, like darude - sandstorm:
 
1.
HDA
Acronym for "Hammered Dog Ass". Completely lacking in aesthetic merit, extremely ugly, displeasing to the eye and viscera. The resulting visual summary of an already homely subject after a losing impact with something large, heavy and iron.

May also be used to express feeling under the weather, i.e. "I feel like____."
M: That girl was pretty cute last night man, it's a shame I wasn't able to go home with her.

B: On the contrary, she had the beak of a falcon, no chin, and a dusky mustache. She looked like HDA, (Hammered Dog Ass.)
by bwho November 10, 2008
 
2.
HDA
"Hit Dat Ass"
"ey' man, I see you talkin' to ol' bird over there. HDA or wha'"
by C40 December 08, 2011
 
3.
HDA
Head Disk Assembly, the part of a computer's hard drive which stores the data.
Typically when a drive experiences the Click of Death (ake the OMGWTF I just lost my data) noise the head comes in contact with the disk due to the collapse of the micrometre thickess air bearing from contact with a particle, resulting in massive damage known as a head crash.

Normally the end result is a bricked hard drive, which is recoverable if you are lucky and have a couple of K$ to spend on data recovery in a clean room.

Interestingly a hard disk will instantly crash if opened up and smoke blown onto the disk while spinning, useful for demonstration purposes but ruins the drive

Sometimes a failed drive can be salvaged by the careful replacement of the head assembly from a donor drive, this is a last resort and can make things worse in most cases.
Dude, your HDA just went flatline. Hope you have backups.
by conundrum8472 September 24, 2010
 
4.
"HIGH DEFINITION ASS"
The perfect ass in jeans!
"Holy smokes, check out the HDA on her."
by EH&CH October 14, 2008
 
5.
HDA
Hands-Down Adorable- someone who is so cute it's almost unbearable
I think every American girl agrees that Michael Cera is HDA.
by clockiewitch July 02, 2009