Piss (verb)

1. Urinate.
2. Express anger, contempt or disappointment.

Origin:

From middle english pissen, from old english pīesan, of germanic origin; related to dutch pissen and german pinkeln.

Examples:

1. He needed to go to the toilet to piss.
2. He was so angry he could hardly piss straight.
3. He couldn't believe she was making him wait and he said he was going to piss himself.
4. The smell of urine made him realize that someone had just pissed on the wall.
5. He was so drunk he didn't realize he was pissing on his own leg.