In a manner that is feminine or lacking in masculine characteristics; with effeminate qualities.
Adverbial form of 'effeminate,' created by adding the standard '-ly' suffix to the adjective. This formation has been stable in English since at least the 17th century.
The fact that English even needed an adverb form of this word shows how much historical energy people spent describing and judging how masculine someone acted—we've created these incredibly specific words for something pretty arbitrary.
Adverbial form embedding the same bias: that feminine deportment, expression, or behavior is a marked deviation from neutral (male) baseline, inherently subject to judgment.
Avoid in evaluative contexts. Use 'in a feminine manner' or 'with feminine presentation' if neutral description needed.
["in a feminine manner","with feminine expression","in a gender-nonconforming way"]
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