the Big Three of lazy, shallow, and incorrect liberal analyses of fascism are "fascism is when authoritarianism" "fascism is when you use dehumanizing language" and fascism is when someone feels disgust"
the actual coherent correct description of fascism is "a reactionary traditionalist nationalist ideology"- more specifically reactionary in the sense of trying to restore pre-liberal social forms (instead of just restoring earlier forms of liberalism) and nationalist in an exclusionary manner- (ethno-nationalist or religious-nationalist rather than civic-nationalist, seeking to strip citizens of racial or religious minorities of their equal citizenship)
this is both borne out by how self-identified fascists behave, and also by how they describe their own politics. "reactionary" "nationalist" and "traditionalist" are all terms they regularly use to describe themselves.
maybe you could narrow the definition further and say it should only refer to reactionary traditionalist nationalism that draws influence from hitler and mussolini- so for example hindutva wouldn't count- but this is a semantic quibble. whether we consider hindutva ideology to be the south asian form of fascism, or a south asian form of reactionary traditionalist nationalism which is equivalent to (but distinct from) fascism, it's just as vile either way.
but liberals naturally don't care about any of this, they just want an excuse to say "that woman on the bus told me to stop jerking off in front of her (authoritarianism!) and called me disgusting (disgust based politics!) and said I was acting like an animal! (dehumanization!) she is LITERALLY Hitler!"
respectfully I don't think this is a coherent definition either. this conflates what fascists (commonly) claim to do with what successful fascist movements actually do; restoring pre-liberal economic and social forms is a chimera which every fascist movement faced with the reality of power has not actually attempted, the corporatist state as was developed through the 20s by the PNF and followed from their respective distances by the NSDAP, VF, FE de las JONS, Garda de Fier, and even some of the post-war neocolonial dictatorships which are often considered to have been fascist. Early fascism in italy had a significant influence from futurist figures which were the polar opposite of traditionalist pre-liberal-isms, while in other places like Spain and Germany there was influence from movements that were almost comically regressive, such as carlists or the volkisch movement (both of which predated the preconditions structurally needed for fascism to exist!). One can spend a lot of time listing off trivia of the influences and genealogy of early fascism, because the actual behavior of successful fascist movements is to form an ideological amalgam under which monopoly capital can persist under crisis conditions once bourgeois-democratic mediation becomes a liability to the reproduction of capital.
the fact that capitalism's own contradictory development is what leads it to the conditions of revolutionary crisis that spell its death is the reason why so many reactionary elements that oppose proletarian organization take this "turn back the clock" ideological approach, but this by itself doesn't make turning back the clock a sustainable political program by any movement which holds power. If we don't take bourgeois liberalism's word that it rules for the "people", I don't see why the terms most often used by fascist movements should be anything more than a hint of the purpose they actually serve in a capitalist society. of the terms you propose, traditionalism I think has the biggest fuzziness issue similar to the fascist label itself; the content of "traditionalism" in one context will only have in common with the traditionalism of another context what those two contexts have in common in the first place, i.e. there is no stable "traditionalist" program that can be identified across history and space. I have plenty of qualms with Dimitrov and the 6th/7th congress of the comintern, but their definition (the open terrorist dictatorship of the most reactionary, most chauvinistic, most imperialist elements of finance capital) does put at the forefront the specific context of the crisis of imperialist capitalism, which is much more important for anti-fascist purposes than pinning down its fuzzy and shifting ideological form.
