them·self (thĕm-sĕlf, thəm-)
a. Himself or herself. Used as a singular gender-neutral reflexive pronoun to refer to the one previously mentioned or implied, especially as a substitute for generic himself: “Relationships are hard, but all the work is worth it, unless the person you're with has totally let themself go” (John Metz).
b. Used as a singular reflexive personal pronoun for someone who does not identify as either male or female. See Usage Note at they.
2. Nonstandard Themselves: “I was telling Bubber how he and my uncles owns the whole place themself” (Carson McCullers).
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