boundary-n; 3 Senses

Sense Number 1: a line that serves as a demarcation between regions

Commentary: BOUNDARY[+location][+line][+demarcation]
NOTE: refers to a demarcation between two adjoining regions
NOTE: answers the question 'where?'

Authorities picked the man up when he tried to cross an international boundary.
This fence marks the boundary of John's property.
She could not cross the emotional boundaries he had set up around himself. (where the barrier is)

WordNet 3.0 Sense Numbers: 1, 2

Sense Number 2: the greatest possible degree of something

Commentary: BOUNDARY[+quantity][+extent][+maximum][+limit]
NOTE: often used in the plural
NOTE: refers to a maximum degree or limit of something
NOTE: answers the question 'how far?'

His behavior at the party was beyond the boundaries of civilized conduct.
Mary thinks these clothing styles are barely within the boundaries of good taste.
Their research has pushed the boundary of our understanding of this disease. (the limit)
John believes there are no boundaries to technological innovation. (how far it can go)

WordNet 3.0 Sense Numbers: 3

Sense Number 3: none of the above

Commentary: Automatically generated NOTA sense (bbn)