| 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. |
acetal ac·e·tal (ās'ĭ-tāl')
n.
A colorless, flammable, volatile liquid used as a solvent.
Any of the compounds formed from aldehydes combined with alcohol.