Why do people think that attacking men isn't sexist?

CoffeeWC
If you look up the definition of sexism in the dictionary, sexism is treating someone differently because of their gender. It really pisses me off when feminists attack men claiming it's not sexist because it's not against women.
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+1 y
According to Merriam Webster:

Definition of sexism

1: prejudice or discrimination based on sexespecially : discrimination against women

2: behavior, conditions, or attitudes that foster stereotypes of social roles based on sex

Why do people think that attacking men isn't sexist?
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