\Di*men"sion\, n. [L. dimensio, fr. dimensus, p. p. of
dimetiri to measure out; di- = dis- + metiri to measure: cf.
F. dimension. See {Measure}.]
1. Measure in a single line, as length, breadth, height,
   thickness, or circumference; extension; measurement; --
   usually, in the plural, measure in length and breadth, or
   in length, breadth, and thickness; extent; size; as, the
   dimensions of a room, or of a ship; the dimensions of a
   farm, of a kingdom.
         Gentlemen of more than ordinary dimensions. --W.
                                               Irving.
{Space of dimension}, extension that has length but no
   breadth or thickness; a straight or curved line.
{Space of two dimensions}, extension which has length and
   breadth, but no thickness; a plane or curved surface.
{Space of three dimensions}, extension which has length,
   breadth, and thickness; a solid.
{Space of four dimensions}, as imaginary kind of extension,
   which is assumed to have length, breadth, thickness, and
   also a fourth imaginary dimension. Space of five or six,
   or more dimensions is also sometimes assumed in
   mathematics.
2. Extent; reach; scope; importance; as, a project of large
   dimensions.
3. (Math.) The degree of manifoldness of a quantity; as, time
   is quantity having one dimension; volume has three
   dimensions, relative to extension.
4. (Alg.) A literal factor, as numbered in characterizing a
   term. The term dimensions forms with the cardinal numbers
   a phrase equivalent to degree with the ordinal; thus,
   a^{2}b^{2}c is a term of five dimensions, or of the fifth
   degree.
5. pl. (Phys.) The manifoldness with which the fundamental
   units of time, length, and mass are involved in
   determining the units of other physical quantities.
Note: Thus, since the unit of velocity varies directly as the
      unit of length and inversely as the unit of time, the
      dimensions of velocity are said to be length [divby]
      time; the dimensions of work are mass [times]
      (length)^{2} [divby] (time)^{2}; the dimensions of
      density are mass [divby] (length)^{3}.
{Dimension lumber}, {Dimension scantling}, or {Dimension
stock} (Carp.), lumber for building, etc., cut to the sizes
   usually in demand, or to special sizes as ordered.
{Dimension stone}, stone delivered from the quarry rough, but
   brought to such sizes as are requisite for cutting to
   dimensions given.