peek·a·boo 
(pēkə-b′)
(pēkə-b′)n.
A game for amusing a small child, in which one covers one's face or hides and then returns to view saying "Peekaboo!"
adj.
1. Decorated with embroidered holes or eyelets.
2. Made of a sheer or transparent fabric.
[PEEK + BOO1.]