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mansplaining

n. (context colloquial chiefly Internet English) An act of mansplaining. vb. (present participle of mansplain English)

Wikipedia
Mansplaining

Mansplaining is a portmanteau of the words man and explaining, defined as "to explain something to someone, typically a man to woman, in a manner regarded as condescending or patronizing." Lily Rothman of The Atlantic defines it as "explaining without regard to the fact that the explainee knows more than the explainer, often done by a man to a woman." and feminist author and essayist Rebecca Solnit ascribes the phenomenon to a combination of "overconfidence and cluelessness."

Due to its gender-specific reference to "man", this term has been referred to by some critics as inherently sexist.