hostility-n; 2 Senses

Sense Number 1: a state or attitude of unfriendly opposition

Commentary: HOSTILITY[+state][+opposition][+unfriendly]

Her hostility to the idea was evident from her facial expression.
There was no hostility in his voice when he pointed out the flaws with Bob's performance.
The village's general hostility to all outsiders made if difficult to conduct an anthropologic study.
John has developed a hostility to salesmen of all kinds.

WordNet 3.0 Sense Numbers: 1, 2, 3

Sense Number 2: a fight, violent confrontation

Commentary: HOSTILITY[+activity][+violent][+fight]
NOTE: often occurs in plural

The hostilities finally ended with the signing of the treaty.
The U.N. called for an immediate cessation of hostilities
The mayor could do little to quiet the explosive racial hostility on the south side.
Broken glass in front of shops was further evidence of yesterday's hostility against the meeting of the World Trade Organization.

WordNet 3.0 Sense Numbers: 4