In addition to the punctuation mark that we all recognise, sometimes in places we wish we didn’t, there is also a literary device, a figure of speech that also goes by the name apostrophe.
With its roots in Greek drama and the Greek language (meaning ‘turning away’), apostrophe is the rhetorical act of addressing a third party in a speech or piece of poetry or prose.
It can be used to add some emotive power to discussions of abstract ideas, such as John Donne’s references to Death in one of his Holy Sonnets: ‘Death be not proud, though some have called thee/Mighty and dreadful’.
It can also be used to drive a rhetorical point home to one group, while apparently addressing an (absent) third party.
The kind of speech in which a politician has a message for ‘the fat cats at City Hall’, but is actually looking for a response from the ‘ordinary working people’ that might hear the speech.
Just as the punctuation apostrophe shows were some letters might have been omitted, the literary device is also highlighting an absence.
Examples of apostrophe as figure of speech
Hello, darkness, my old friend/I’ve come to talk with you again (Paul Simon, The Sound of Silence)
Milton! thou shouldst be living at this hour (William Wordsworth, Milton)