If you describe a person or their views as revisionist, you mean that they reject traditionally held beliefs about a particular historical event or events.
[formal]
Revisionist history must be challenged by historical research.
...the revisionist interpretation of the French Revolution.
A revisionist is a person who has revisionist views.
[formal]
The reputation of the navigator is under assault from historical revisionists.
2. adjective
If a socialist describes another socialist's actions or opinions as revisionist, they mean that they are unacceptable because they are more moderate than normal Marxist theory allows.
[formal, disapproval]
This revisionist thesis departs even further from Marxist assertions.
A revisionist is a person who has revisionist views.
[formal]
...ferocious infighting between Stalinist hardliners and revisionists.
revisionist in American English
(rɪˈvɪʒɪst)
noun
1.
a person who revises, or favors the revision of, some accepted theory, doctrine, etc.