The Collaborative International Dictionary of English v.0.48:

Multiple \Mul"ti*ple\, n. (Math.)
   A quantity containing another quantity an integral number of
   times without a remainder.
   [1913 Webster]

   Note: A

   common multiple of two or more numbers contains each of
      them a number of times exactly; thus, 24 is a common
      multiple of 3 and 4. The

   least common multiple is the smallest number that will do
      this; thus, 12 is the least common multiple of 3 and 4
      (abbreviated LCM).
      [1913 Webster]

WordNet (r) 3.0 (2006):

least common multiple
    n 1: the smallest multiple that is exactly divisible by every
         member of a set of numbers; "the least common multiple of
         12 and 18 is 36" [syn: lowest common multiple, least
         common multiple, lcm]