Related Clues:

• Narrow opening to separate when penniless
• Use a razor blade on, perhaps
• Key is certainly in hole
• Use a box cutter on
• Open with a box cutter
• Buttonhole, say
• Cut with a razor blade
• Crack (in rock)
• Pupil of a lizard, e.g
• Not much light can get through it
• X-Acto knife cut, perhaps
• Cut some tasteless literature
• Use an X-Acto Knife on
• Cat's pupil, on a sunny day
• Opening, as after an earthquake