Definition - An interrogative fragment that is appended to statements to turn them into questions.

1. The types of questions that result from this are called tag questions.

Example -
He likes me, doesn't he?
In the above, the doesn't he is the tag that turns the statement He likes me into a tag question.

Oxford English Dictionary -
The term's first citation is from 1957:
"An understanding of tags implies an understanding of sentence order and the role of accent."
(Publ. Amer. Dial. Soc. xxviii. 17)

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