unwrinkle

un- +‎ wrinkle

unwrinkle (third-person singular simple present unwrinkles, present participle unwrinkling, simple past and past participle unwrinkled)

1. (transitive) To remove wrinkles from.
   • 1935, Elizabeth Bowen, The House in Paris, New York: Vintage, 1957, Part Two, p. 140,

     He and she sat side by side like two wax people while the waiter stretched across to unwrinkle the tablecloth and straighten the knives.

   • 2000, Gary Soto, Nickel and Dime, Albuquerque: University of New Mexico Press, Part 2, p. 85,

     The job was done before Silver could unwrinkle the grimace on his face.

2. (intransitive) To stop being wrinkly; to become flat or smooth.
   • 1959, Mervyn Peake, Titus Alone, New York: Ballantine, 1968, Chapter 66, p. 179,

     His head protruded out of his torn collar much as the head of the tortoise protrudes from its shell, the throat unwrinkling, the eyes like beads, or pips of jet.

   • 1987, Derek Walcott, “Cul de Sac Valley” in The Arkansas Testament, New York: Farrar, Straus and Giroux, p. 11,

     In a rain barrel, water

     unwrinkles to glass;

     a lime tree’s daughter

     there studies her face.

   • 1996, Charles Mathes, The Girl Who Remembered Snow, New York: St. Martin’s Press, Chapter 15, p. 212,

     Emma went through the closet and removed the black gabardine jacket she had hung up to unwrinkle.

• (remove wrinkles from): flatten out, smooth