The Collaborative International Dictionary of English v.0.48:

lcm \lcm\ n.
   Abbreviation for the least common multiple, the smallest
   multiple that is exactly divisible by every member of a set
   of numbers; as, the least common multiple of 12 and 18 is 36.
   [abbr.]

   Syn: lowest common multiple, least common multiple.
        [WordNet 1.5]

WordNet (r) 3.0 (2006):

lcm
    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]

V.E.R.A. -- Virtual Entity of Relevant Acronyms (February 2016):

LCM
       LEAF Creation Method (EES, cryptography)