to refuse to use or buy something as a protest is known as
militia
natural law
boycott
repeal
The answer is boycott.
To refuse to use or buy something as a protest is known as a boycott.
Explanation: A boycott is a form of protest in which individuals or groups make a deliberate decision to abstain from using or purchasing a certain product, service, or engaging with a particular company or organization. This protest method is usually done to demonstrate discontent or disapproval towards the actions, policies, or practices of the entity being boycotted. It is a way for people to express their opposition or send a strong message by collectively withholding their support, financial or otherwise.