Singular they has become the pronoun of choice to replace he and she in cases where the gender of the antecedent – the word the pronoun refers to – is unknown, irrelevant, or nonbinary, or where gender needs to be concealed. It’s the word we use for sentences like Everyone loves his mother.

But that’s nothing new. The Oxford English Dictionary traces singular they back to 1375, where it appears in the medieval romance William and the Werewolf. Except for the old-style language of that poem, its use of singular they to refer to an unnamed person seems very modern. Here’s the Middle English version: ‘Hastely hiȝed eche . . . þei neyȝþed so neiȝh . . . þere william & his worþi lef were liand i-fere.’ In modern English, that’s: ‘Each man hurried . . . till they drew near . . . where William and his darling were lying together.’

Since forms may exist in speech long before they’re written down, it’s likely that singular they was common even before the late fourteenth century. That makes an old form even older.

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