A word meaning cool, a 'tall' person can do anything they want, wherever they want, whenever they want: rules do not apply to a 'tall' person, since they are so amazing.
The origin of this meaning was used first at a Harkins Theatre, when a customer asked for, instead of a small, a tall drink (such as
the smallest size at coffee shops). Ever since, it has been used to describe how
incredible something is.