What is "tobacco mosaic virus"

Mosaic \Mo*sa"ic\, n. [F. mosa["i]que; cf. Pr. mozaic, musec, Sp. & Pg. mosaico, It. mosaico, musaico, LGr. ?, ?, L. musivum; all fr. Gr. ? belonging to the Muses. See Muse the goddess.]

1. (Fine Arts) A surface decoration made by inlaying in patterns small pieces of variously colored glass, stone, or other material; -- called also mosaic work.

2. A picture or design made in mosaic; an article decorated in mosaic.

3. Something resembling a mosaic[1]; something made up of different pieces, fitted together by design to form a unified composition.

   aerial mosaic An aerial photograph of a large area, made by carefully fitting together aerial photographs of smaller areas so that the edges match in location, and the whole provides a continuous image of the larger area. Called also

   mosaic map and photomosaic.

   mosaic virus A type of plant virus that causes green and yellow mottling of leaves of a plant. A much-studied type is the tobacco mosaic virus, affecting the tobacco plant.

n. the widely studied plant virus that causes tobacco mosaic; it was the first virus discovered (1892) [syn: TMV]

Tobacco mosaic virus (TMV) is a positive-sense single stranded RNA virus that infects a wide range of plants, especially tobacco and other members of the family Solanaceae. The infection causes characteristic patterns, such as " mosaic"-like mottling and discoloration on the leaves (hence the name). TMV was the first virus ever to be discovered. Although it was known from the late 19th century that an infectious disease was damaging tobacco crops, it was not until 1930 that the infectious agent was determined to be a virus.