"A little off topic, but I just wanted to jump up and down a little waving my arms in frantic protest over [another poster]'s insistence that various "isms" - sexism, racism, what have you - are monodirectional.
For one thing, it's problematic because this isn't the way the vast majority of people use these words. For just about everyone (not to mention every dictionary under the sun) racism (to choose an example) is prejudice or discrimination based on race, full stop. Limiting the word to institutional prejudice or discrimination against specific racial groups in specific cultural contexts creates all kind of confusion - not least because not all the world is made up of the kind of neat binary hierarchies of oppression this kind of definition demands.
For another, society is not a monolith. Even if racism is by definition cultural and institutional, the idea that every institution and sub-culture within a society shares the same biases isn't really tenable.
To return to sexism, far simpler to say (as the OED does, actually) that it is sex-based prejudice and discrimination almost always directed against women."
This poster isn't the first to make this spurious argument and zie won't be the last.
Disagree however you want, but the prejudice+power definition of -isms are sociological in nature and correct. The "vast majority" of people can use a technical term however they want, that doesn't mean they are using it correctly. Perfect example: paradigm shift. This is a technical term, used in scientific disciplines to indicate a sudden and complete change in how the world is viewed by a sub-group of humanity, and in Western culture, can be applied directly to inventions of mass media and mass communication and the effect this had on how the culture as a whole related to the world. In popular lexicon, we use it to indicate a change in how we behave personally, akin to "changing gears" or changing the flow of our lives. It has also been appropriated by motivational speakers for large corporations as a term to get corporate teams to expand their way of working. If one compares the two usages, they seem to have the same basic meaning, but one is technically correct within the context that spawned it, and one is popular misconception and appropriation of the first.
By referencing "every dictionary under the sun", I assume that means zie has read every dictionary under the sun. I doubt this, mainly because if zie had, zie would have noticed that most regular dictionaries are mainly catalogs of common usage in a specific arena, and do not mean the be-all end-all of a word. There is a reason that we have medical and legal dictionaries, as well as dictionaries for different disciplines. These dictionaries may have a word that is spelled the same in each of them, but based on the context, has a differing meaning. Hell, the meaning of a word can differ across languages. Some words don't translate directly from language to language, and some languages have words that others do not. Does this mean that the basic concept does not exist from culture to culture? No, it means that the concepts are viewed differently through different cultural lenses.
Suggesting that your preferred definition of isms is inherently more correct at all times is intellectually dishonest.
In actuality, you can indeed see the binary hierarchies almost world-wide, with adjustments of the standard to the specific group. Example: racial binary, between "white" and "non-white" does exist in most places that I have studied or visited. White in some areas may not look quite like it looks here, but it plays the same role. It can be found echoed through out most institutions and sub-cultures to a greater or lesser degree. The binary hierarchy of sex is also present world wide to differing degrees, even with differences in the definition of masculine v. feminine.
This poster seems to desire the simpler explanation at the expense of dismissing actual intellectual effort on hir part to challenge hir own small view of how the world works.
Sexism is not in the eye of the beholder
Let it be assumed for the purposes of this space, that the definition of -isms are the power+prejudice equation.