Definition - A language form that denotes only one thing.

Example -
In the phrase that dog, the word dog is in its singular form.

Etymology -
The word derives via Old French from the Latin singularis, single or solitary.

Oxford English Dictionary -
Its first citation in its grammatical sense is from 1387:
"Everiche in þe singuler nombre was i-cleped Anthiochus."
(Trevisa Higden (Rolls) IV. 17)

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