Self-masturbation

1. When someone performs the act of masturbation on themselves.

2. When someone acts like an arrogant twat and tries to present themselves as being smarter, cooler or more important than they actually are, typically by being boastful and/or putting other people down.

This is most often seen online, but can also happen in real life.

1. John performed a little self-masturbation when he got home to relax.

2. Hank bragging about his supposedly high IQ and over-relying on five-dollar words came across as major self-masturbation in the YouTube comments section.