IMO it is interchangeable with "nationalist" to them and gives them the semantic cover to deny they are trying to destroy any nation they are in.
They tell you who they are and what they believe if you listen and watch.
"Destroy our nations" or "Destroy all nations" depending how you hear it.
The red and black flags are communist, anarchist, syndicalist, all branches from the same tree.
There is another term that better fits what many if not most anti-fascist are; nihilists.
Here is a scan of an 1886 edition of Webster's:
The words fascism and fascist don't exist yet.
These do:
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If the description of "Socialism" seems a bit benign or even positive, the rot had already set in even then.
From the Biographical section of that edition:
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