Wikipedia
Dress-up is a game played mainly by children. It involves dressing up, usually to impersonate someone or something, like an animal or character in a fairy tale. The type of clothes they dress up in often resembles who they are trying to be, either adults' clothing or special play clothes designed specifically for dress-up like feather boas and jewelry.
More and more tweens are taking to the internet to talk with friends, shop and play games. In recent years, the most popular girls games have been dress up and fashion games which allow girls to dress and customize virtual dolls, go shopping and complete challenges. The newest virtual dress up sites allow users to make new friends and chat with other users while they play with their pretend dolls.
It is said to help children strengthen their imagination and helps with learning, since it is a form of make-believe and role-playing. The game is most popular among girls, usually from ages 2–8.
Usage examples of "dress-up".
Had the circumstances been happier, Ada thought, this would have been like the hair contest, a game of dress-up against which they might wager to see who could accouter herself most convincing as a man.
Snowdon dress the children in rational little outfits, in bright, happy colors that matched, no stripes disagreeing with plaids, no unsanctioned dress-up boas and diamond tiaras and space-gear stun guns strapped to pipe-cleaner hips.
The people's dress-up clothes did have their whiteness enlivened by fancy embroidery, and the patterns and colors of that decoration did vary from place to place.