The Collaborative International Dictionary of English v.0.48:

Elemental \El`e*men"tal\ ([e^]l`[-e]*m[e^]n"tal), a.
   1. Pertaining to the elements, first principles, and primary
      ingredients, or to the four supposed elements of the
      material world; as, elemental air. "Elemental strife."
      --Pope.
      [1913 Webster]

   2. Pertaining to rudiments or first principles; rudimentary;
      elementary. "The elemental rules of erudition."
      --Cawthorn.
      [1913 Webster]

WordNet (r) 3.0 (2006):

elemental
    adj 1: relating to or being an element; "elemental sulphur"
    2: relating to severe atmospheric conditions; "a race against
       hail or cold rains or some other elemental catastrophe"-
       J.K.Howard
    3: of or being the essential or basic part; "an elementary need
       for love and nurturing" [syn: elementary, elemental,
       primary]