Top Definition
An extremely fit individual who is always at the gym working out. They combine their high load basic exercises with new, complex shit that nobody has ever seen before.

Most often times gym ninjas are guys. However, there have been rare sightings of hot and fit women 'gym ninjettes.'
Everytime I go to the gym, I see the same gym ninja doing that weird cardio ab workout on the half blue ball.
by JimminyJillikers December 03, 2008

The Urban Dictionary Mug

Lotsa space for your liquids.

Buy the mug

The Urban Dictionary Mug

Lotsa space for your liquids.

Buy the mug

The Urban Dictionary Mug

Your favorite word on a white mug.

Create a mug

The Urban Dictionary Mug

One side has the word, one side has the definition. Microwave and dishwasher safe. Lotsa space for your liquids.

Buy the mug

The Urban Dictionary T-Shirt

Soft and offensive. Just like you.

Buy the t-shirt

The Urban Dictionary T-Shirt

Smooth, soft, slim fit American Apparel shirt. Custom printed. 100% fine jersey cotton, except for heather grey (90% cotton).

Buy the t-shirt