| 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. |
provirus pro·vi·rus (prō'vī'rəs, prō-vī'-)
n. pl. pro·vi·rus·es
The precursor or latent form of a virus that is capable of being integrated into the genetic material of a host cell and being replicated with it.