If it becomes larger, it stretches.
If you mean like this, it's called pilling.
When you wash a dress, sometimes it shrinks in the wash.But sometimes after using your dress, it becomes larger. What word do you use?
When you buy a T-shirt after using it if the material is not good there are some small cloth balls on your T-shirt the same color as the T-shirt itself. What do you call the process? Will you use it in a sentence?
*Not a teacher*
The most common antonyms for "shrink" are: "increase" and "expand" "Expand" is probably the better choice in the context of a result of washing a piece of clothing.
Last edited by hombre viejo; 20-Jan-2013 at 23:07. Reason: failed to note that I'm not a teacher.
When talking about clothing, I would only use "stretch" regardless of whether it stretched from over-wearing or from washing.