abhorrence
abomination
aggression
aggressiveness
allergy
animosity
animus
annulling
antipathy
antithesis
argumentation
aversion
backlash
bad blood
bellicism
bellicosity
belligerence
belligerency
chauvinism
clash
clashing
cold sweat
collision
combativeness
competition
con
conflict
confrontation
confutation
contention
contentiousness
contradiction
contradistinction
contraindication
contraposition
contrariety
contrariness
contrast
controversy
counteraction
counterposition
counterworking
crankiness
creeping flesh
cross-purposes
crotchetiness
despitefulness
difference
disaccord
disaccordance
dislike
enmity
hinderance
hindrance
hostility
ill will
interference
oppositeness
opposition
disagreement
disapproval
discontent
discord
envy
hate
irritation
mistrust
prejudice
repugnance
repulsion
resentment
rivalry