apostrophe (rhetoric)
Definition - A figure of speech where the speaker or writer stops in mid-discourse and addresses someone or something who is either present or absent.

Example -
Oh, Joe Dimaggio, where did you go!

Etymology -
The word derives via Middle French and Late Latin from the Greek apostrophos, a turning away (from apo, from + strephein, to turn).
Note: Originally, it denoted an invocation spoken at the beginning of an epic, such as Homer's Iliad.

Oxford English Dictionary -
Its first citation in this sense is from 1533:
"With a fygure of apostrophe and turning his tale to God criyng out: O good Lorde."
(More Apol. vii. Wks. 1557, 859/1)

Quotation -
"As explained by Quintilian, apostrophe was directed to a person present; modern use has extended it to the absent or dead (who are for the nonce supposed to be present); but it is by no means confined to these, as sometimes erroneously stated."
(Source: OED s.v. apostrophe)

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