In sewing, a tuck is a fold or pleat in fabric that is sewn or fastened in place.
When the tucks are very narrow, they are called pintucks or Pin-tucking.
Tucks are also used to shorten a finished garment, especially a child's garment, so that it may be lengthened ("let down") as the child grows by removing the stitching holding the tuck in place.
In Louisa May Alcott's Little Women, Amy says: "My only comfort," she said to Meg, with tears in her eyes, "is that Mother doesn't take tucks in my dresses whenever I'm naughty, as Maria Parks's mother does.
My dear, it's really dreadful, for sometimes she is so bad her frock is up to her knees, and she can't come to school.Tucks, made easy with the invention of the sewing machine, were very popular as ornamentation in the latter half of the 19th century, especially in fine linen or cotton fabric for chemisettes, engageantes, blouses, lingerie, summer dresses, and children's garments.