Dictionary.com
–noun
1.
an athletic activity requiring skill or physical prowess and often of a competitive nature, as racing, baseball, tennis, golf, bowling, wrestling, boxing, hunting, fishing, etc.---According to this it isnt
3.
diversion; recreation; pleasant pastime.----According to this it is
Answers.com
Physical activity that is governed by a set of rules or customs and often engaged in competitively.---According to this it is
A particular form of this activity.---According to this it is
An activity involving physical exertion and skill that is governed by a set of rules or customs and often undertaken competitively.
An active pastime; recreation.---According to this it isntSo it ultimately boils down to if you think a sport requires physical activity or not.
In order to define whether or not chess is a sport, we must first determine what makes something a sport.
So is physical activity required for something to be a sport? That is ultimate question here.