A discussion elsewhere yesterday uncovered the fact that a lot of people dislike terms like 'cisgender' when used in otherwise jargon-free conversation, because they feel it is somehow elitist (as would be your reference to the knapsack, because if you haven't come across the essay or references to it - and a lot of people haven't - it's effectively meaningless). I can vaguely see their point, because it isn't a word everyone is familiar with, and I read the comments above about etymology with mostly-amused interest, but there really isn't a better single word to use so... *shrug*
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