All 11 Uses

prologue
in
A Midsummer Night's Dream
(Edited)

Write me a prologue; and let the prologue seem to say we will do no harm with our swords, and that Pyramus is not killed indeed; and for the more better assurance, tell them that I Pyramus am not Pyramus but Bottom the weaver: this will put them out of fear.
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prologue = introduction
...and let the prologue seem to say we will do no harm with our swords, and that...
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Well, we will have such a prologue; and it shall be written in eight and six.
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Therefore another prologue must tell he is not a lion.
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So please your grace, the prologue is address'd.
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He hath rid his prologue like a rough colt; he knows not the stop.
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Indeed he hath played on this prologue like a child on a recorder; a sound, but not in government.
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Uses with a meaning too rare to warrant foucs:

Enter PROLOGUE.
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prologue = the name of a character who delivers a prologue in the play within the play
PROLOGUE: 'If we offend, it is with our good will.'
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PROLOGUE: Gentles, perchance you wonder at this show; But wonder on, till truth make all things plain.
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Exeunt PROLOGUE, THISBE, LION, and MOONSHINE.
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Definitions:

(1) (prologue)
an introduction to a fictional work; or anything that precedes a more important event
(2) (meaning too rare to warrant focus)
Rarely, prologue can be used in other senses. For example, in Shakespeare's A Midsummer Night's Dream, Prologue is the name of a character who delivers a prologue in a play within the play.