What is the significance and origin of the title of the play, A Midsummer Night's Dream?

Shakespeare had a lot of fun with the whole idea of summertime, fantasy, and dreams throughout A Midsummer Night’s Dream. The title itself would have immediately clued his original audience into the fact the play took place on June 23rd, the summer solstice, then called ‘midsummer.’ In Shakespeare’s time this was a special day of feasting and celebration. The Elizabethan people were generally superstitious, and some believed the summer solstice was an especially magical time. Festivals celebrated fertility, and often famous stories were re-enacted, such as St. George and the Dragon. Sometimes bones were burned, thus giving us the term ‘bonfire.’

The title could also refer to three different dreams possibilities within the play itself. First is a reference to the unfortunate Bottom, who when in donkey state couldn’t believe that Titania, the lovely Queen of the Fairies, actually fell in love with him. The next day he puzzled over everything he remembered, deciding it must have been an odd dream:

“I have had a dream, past the wit of man to
say what dream it was: man is but an ass, if he go
about to expound this dream. Methought I was--there
is no man can tell what. Methought I was,--and
methought I had,--but man is but a patched fool, if
he will offer to say what methought I had. The eye
of man hath not heard, the ear of man hath not
seen, man's hand is not able to taste, his tongue
to conceive, nor his heart to report, what my dream
was.”

The second dream-like reference might be the four young lovers whose lives get unbearably tangled when Puck completely mixes up Oberon’s instructions and the wrong people fall in love with the wrong people. The next day they are confused and think they must have been dreaming. Demetrius says, “Are you sure/ that we are awake? It seems to me/That yet we sleep, we dream.” And as they return to the duke’s home, Demetrius continues: “Why, then, we are awake: let's follow him/ And by the way let us recount our dreams.”

Finally, at the very end of the play, the prankster Puck addresses the audience and suggests that they have actually dreamt the entire play themselves:

“If we shadows have offended,
Think but this, and all is mended,
That you have but slumber'd here
While these visions did appear.
And this weak and idle theme,
No more yielding but a dream…”

So the title A Midsummer Night’s Dream aptly captures the magical, dream-like, and ultimately joyful tone of the entire work.