register (linguistics)

In linguistics, a register is a subset of a language used for a particular purpose or in a particular social setting. For example, an English speaker may adhere more closely to prescribed grammar, pronounce words ending in -ing with a velar nasal (e.g. "walking", not "walkin'") and refrain from using the word "ain't" when speaking in a formal setting, but the same person could violate all of these prescriptions in an informal setting.
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