peekaboo

thumb|Two children playing peekaboo (1895 painting by Georgios Jakobides)

Peekaboo (also spelled peek-a-boo) is a simple game played with an infant. To play, one player hides their face, pops back into the view of the other, and says Peekaboo!, sometimes followed by I see you! There are many variations: for example, where trees are involved, "Hiding behind that tree!" is sometimes added. Another variation involves saying "Where's the baby?" while the face is covered and "There's the baby!" when uncovering the face.