Fluids

Bodies which po e no elasticity of form. Liquids and gases are fluids, and as they require no force to keep them in any particular shape, they exercise no permanent resistance to a change of shape. According to Maxwell, a fluid is a body the contiguous parts of which act on one another with a pre ure which is perpendicular to the interface which separates those parts. While this may be true in the case of many fluids when at rest, it is never strictly so when the body is in motion. We have then no perfect fluids; in other words, there is always some degree of viscosity. Fluitant. Floating plants or parts of plants. Flukes. See TREMATODA.