| a calculus or concretion found in the stomach or intestines of certain animals, esp. ruminants, formerly reputed to be an effective remedy for poison. |
| a screen or mat covered with a dark material for shielding a camera lens from excess light or glare. |
| asphalt (ās'fôlt') Pronunciation Key
A thick, sticky, dark-brown mixture of petroleum tars used in paving, roofing, and waterproofing. Asphalt is produced as a byproduct in refining petroleum or is found in natural beds. |