| a screen or mat covered with a dark material for shielding a camera lens from excess light or glare. |
| an extraordinary or unusual thing, person, or event; an exceptional example or instance. |
retraction re·trac·tion (rĭ-trāk'shən)
n.
The act of drawing back or in; shrinking.
The act of pulling apart, usually as part of a surgical procedure.
The posterior movement of teeth, usually with the aid of an orthodontic appliance.