Usage Note
Soltera is the feminine form; the masculine is soltero. Both can also function as adjectives: está soltera (she is single). In formal documents and surveys estado civil: soltero/a marks unmarried status. The word carries no negative connotation in modern usage, unlike the dated English 'spinster', which solterona (emphatic, somewhat pejorative) more closely mirrors.
Examples
"Su hermana mayor sigue soltera."
Natural Translation
Her older sister is still single.

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