unfold

• (Received Pronunciation) IPA^(key): /ʌnˈfəʊld/
• (General American) IPA^(key): /ʌnˈfoʊld/
• Rhymes: -əʊld

From Middle English unfolden, from Old English unfealdan (“to unfold”), equivalent to un- +‎ fold.

unfold (third-person singular simple present unfolds, present participle unfolding, simple past and past participle unfolded)

1. To undo a folding.
   • Herbert

     Unfold thy forehead gathered into frowns.

   • 1963, Margery Allingham, chapter 19, in The China Governess‎:

     Meanwhile Nanny Broome was recovering from her initial panic and seemed anxious to make up for any kudos she might have lost, by exerting her personality to the utmost. She took the policeman's helmet and placed it on a chair, and unfolded his tunic to shake it and fold it up again for him.

   to unfold a map; to unfold a tablecloth; she unpacks the new dress and unfolds it carefully

2. (intransitive) To turn out; to happen; to develop.
   • 2012 November 8, Scott Tobias, “Memento’s puzzle structure hides big twists and bigger profundities”, in The AV Club‎:

     Memento unfolds over 22 scenes—or, more accurately, 22 strands of time, the main strand (in color) moving backward in increments, and another strand (in black and white) going forward, though the two overlap profoundly.

3. (transitive) To reveal.
   • c. 1599–1602, William Shakespeare, “The Tragedie of Hamlet, Prince of Denmarke”, in Mr. William Shakespeares Comedies, Histories, & Tragedies: Published According to the True Originall Copies (First Folio), London: Printed by Isaac Iaggard, and Ed[ward] Blount, published 1623, OCLC 606515358, (please specify the act number in uppercase Roman numerals):

     , I.v.

     Pity me not, but lend thy serious hearing  To what I shall unfold.

4. To open (anything covered or closed); to lay open to view or contemplation; to bring out in all the details, or by successive development.
   • William Shakespeare

     Unfold the passion of my love.

   to unfold one's designs;  to unfold the principles of a science

5. To release from a fold or pen.

   to unfold sheep

• fold

unfold (plural unfolds)

1. (computing, programming) In functional programming, a kind of higher-order function that is the opposite of a fold.