The flatworms, or Platyhelminthes, Plathelminthes, or platyhelminths (from the Greek ÏÎ»Î±ÏÏ, platy, meaning flat and á¼Î»Î¼Î¹Î½Ï (root: á¼Î»Î¼Î¹Î½Î¸-), helminth- , meaning worm) are a phylum of relatively simple bilaterian, unsegmented, soft-bodied invertebrates.hey have about 11,000 species, more than all other platyhelminthes combined, and second only to roundworms among parasites on metazoans. Adults usually have two holdfasts, a ring around the mouth and a larger sucker midway along what would be the underside in a free-living flatworm.
square root. (MATHEMATICS) each positive number has another number that, when multiplied times itself, equals that number. So, for example, 4 has a square root of 2 (2 x 2 = 4). The square root of a negative number is an imaginary number. Imaginary numbers are not, by themselves, useful solutions to math problems; but they can be used to find them. BILL: Anna, we have a rectangle that's 3 x as long as it is wide, and it encloses an area of 300 square meters.
The square root of the square root of the square root of something is called the 8th root.