antagonism
antipathy
antithesis
clashing
collision
con
conflict
confrontation
contradiction
contraindication
contraposition
contrariety
contrast
counterposition
cross-purposes
demarcation
differentiation
disagreement
discrepancy
distinction
distinctiveness
distinguishment
division
hairsplitting
hostility
inconsistency
inimicalness
microscopic distinction
nice distinction
nuance
oppositeness
opposition
opposure
oppugnance
oppugnancy
perversity
polarity
repugnance
segregation
separation
shade of difference
showdown
subtle distinction
trichoschistism
contradistinguish
defilade
demurrer
descend
kickoff
proach