Apostrophe (poetry)

1) When a character/narrator speaks to a person who is not present.

Like when Juliet speaks to his Romeo (even though he is not there)

O Romeo, Romeo! Wherefore art thou Romeo?

Deny thy father and refuse thy name.

Or, if thou wilt not, be but sworn my love,

And I’ll no longer be a Capulet.

2) When a character speaks to a personified inanimate being, or an abstraction is addressed (spoken to) as if they were present. 

Like when Alexander Pope speaks directly to Envy.

“Envy, be silent and attend!”

—Alexander Pope

Examples

“Envy, be silent and attend!”

—Alexander Pope

"Oh, Death, be not proud." 

— John Donne

"Hello darkness, my old friend

I've come to talk with you again . . .."

—Paul Simon, "The Sounds of Silence

"O Fortune, Fortune! all men call thee fickle; 

if thou art fickle, what dost thou with him that 

is renown'd for faith? Be fickle, Fortune; for then, 

I hope, thou wilt not keep him long, but send him back." 

 — William Shakespeare , Romeo & Juliet

Wild nights - Wild nights! 

BY EMILY DICKINSON

Wild nights - Wild nights!

Were I with thee

Wild nights should be

Our luxury!

Futile - the winds -

To a Heart in port -

Done with the Compass -

Done with the Chart!

Rowing in Eden -

Ah - the Sea!

Might I but moor - tonight -

In thee!