(biochemistry) interference in or inhibition of the physiological action of a chemical substance by another having a similar structure an actively expressed feeling of dislike and hostility the relation between opposing principles or forces or factors; "the inherent antagonism of capitalism and socialism
Antagonism between people is hatred or dislike between them. Antagonisms are instances of this. There is still much antagonism between trades unions and the oil companies Old antagonisms resurfaced. = hostility