standing at attention 

An erect penis. Otherwise known as a boner, hard on, stiffie, woodrow, woody, etc.

After watching porn for a while, my little soldier was standing at attention.

standing at attention by Wiseman July 25, 2006

standing at attention 

In marching band, standing with your feet together, stomach in, chest out, shoulders back, chin up, and eyes with pride. It is very painful after long amounts of time.

After standing at attention for so long, my legs felt like jelly.

standing at attention by dominito July 4, 2012