adj.1. a. Not capable of existing in agreement or harmony with something else: incompatible views on religion.
b. Not capable of living or working together happily or harmoniously; antagonistic: incompatible roommates.
2. Impossible to be held simultaneously by one person: the incompatible offices of prosecutor and judge.
3. Logic That cannot be simultaneously true; mutually exclusive.
4. Medicine a. Producing an undesirable effect when used in combination with a particular substance: a medication that is incompatible with alcohol.
b. Not immunologically compatible: incompatible blood types.