A raw peep (J. "nama-nozoki"; 生ノゾキ) is the name of a kind of mistake in Go - peeping at a cutting point before you know whether or not you want to cut there.
White shouldn't peep at , because cutting at is still a possible good move. The whole point of peeping is to gain a minor advantage by exploiting a minor weakness in the opponent's position, such as peeping at a Lion's Mouth to create a B2 Bomber. Peeping at a cutting point can be worthwhile, if cutting is a bad move -- however, any such approach is fraught with danger. Caution is advisable.
See also Do not peep at cutting points.