Heteronormativity
This video presents the same text shown beside it, spoken and on screen. It adds nothing the text does not say.
State
Heteronormativity is the assumption, built into a society's institutions, that heterosexual attraction is the default and every other orientation departs from it.
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A form that provides only "husband" and "wife" fields encodes the assumption before anyone fills it in.
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The assumption can operate without hostile intent, through defaults nobody examined rather than through decisions anyone made.