DHS

Abbreviation of "Department of Homeland Security"--the a US government agency devoted to maintaining the safety of America.

"Didn't you hear? The DHS got an 'F' on computer security last week... again."

by DragonFyre April 18, 2006

atm

A scientific measure of pressure equivalent to about 14.6959488 pounds per square inch. Abbreviation for "atmosphere." Its is a measurement of how much pressure the atmosphere exerts on an object at sea level (where the pressure would be 1 atm).

There is 2.5818 atm of pressure on that balloon, causing it to shrink from its original size when the pressure was 2 atm.

by DragonFyre September 15, 2005