The act of running from a taxi without paying the fare. Also, the act of cheating a (presumably) honest, hard working man out of money by neglecting to pay for the service he has provided you by fleeing.
The most hard working group of people you will ever meet. Different from a jogger who is just a person either
a) trying to get fit and failing
b) trying to look cool/hot
c) not trying at all
Runners work incredibly hard, they are always training and are the toughest people you will ever meet. I mean come on, who else could finish a 10k x-country meet with a broken arm or become English national schoolgirl champion with a sprained ankle? They are also amazingly kind, sweet understanding, and compassionate because they understand what it is like to be in pain or be disappointed. A true runner is a good sportsman/woman, they do not boast or brag they just help others and be happy for those who beat them. Any competitiveness that they have is just to make their family, friends and coach proud, it is not for themselves. They are also extremely intelligent and have the strongest minds. A runner is a beautiful person inside and out.
In Texas hold'em poker, this means a card that was drawn to help someone's hand. It is generally used in conjunction with the hand the person improved to. For example, if someone hits two cards to make a flush (i.e. improves on the turn and river), then the person is said to hit runner, runner flush.