Source : Webster's Revised Unabridged Dictionary (1913)

Absorption \Ab*sorp"tion\, n. [L. absorptio, fr. absorbere. See
   {Absorb}.]
   1. The act or process of absorbing or sucking in anything, or
      of being absorbed and made to disappear; as, the
      absorption of bodies in a whirlpool, the absorption of a
      smaller tribe into a larger.

   2. (Chem. & Physics) An imbibing or reception by molecular or
      chemical action; as, the absorption of light, heat,
      electricity, etc.

   3. (Physiol.) In living organisms, the process by which the
      materials of growth and nutrition are absorbed and
      conveyed to the tissues and organs.

   4. Entire engrossment or occupation of the mind; as,
      absorption in some employment.

Source : WordNet®

absorption
     n 1: (chemistry) a process in which one substance permeates
          another; a fluid permeates or is dissolved by a liquid
          or solid [syn: {soaking up}]
     2: (physics) the process in which incident radiated energy is
        retained without reflection or transmission on passing
        through a medium; "the absorption of photons by atoms or
        molecules"
     3: the social process of absorbing one cultural group into
        harmony with another [syn: {assimilation}]
     4: the process of absorbing nutrients into the body after
        digestion [syn: {assimilation}]
     5: complete attention; intense mental effort [syn: {concentration},
         {engrossment}, {immersion}]
     6: the mental state of being preoccupied by something [syn: {preoccupation},
         {preoccupancy}, {engrossment}]