adjective / noun
anti
AN-tee/ˈæntˌi/
Opposed to a particular thing or position.
When it comes to logging, the demonstrator by the stump is firmly anti.

Etymology
The prefix anti-, meaning “opposed to,” became a standalone name for an opponent by shortening longer labels. Its earliest recorded use referred to anti-federalists in American politics.
More examples
- Some neighbors are pro, while others are firmly anti.
- The antis at the meeting argue against the new highway.
- Her anti-war views shape the way she votes.
Forms
anti · antis
opposition noun — Disagreement with or resistance to something.