Source : Webster's Revised Unabridged Dictionary (1913)

Leucocyte \Leu"co*cyte\ (l[=u]"k[-o]*s[imac]t), n. [Leuco- + Gr.
   ky`tos a hollow vessel.] (Physiol.)
   A colorless corpuscle, as one of the white blood corpuscles,
   or those found in lymph, marrow of bone, connective tissue,
   etc.

   Note: They all consist of more or less spherical masses of
         protoplasm, without any surrounding membrane or wall,
         and are capable of motion.

Source : WordNet®

leucocyte
     n : blood cells that engulf and digest bacteria and fungi; an
         important part of the body's defense system [syn: {leukocyte},
          {white blood cell}, {white cell}, {white blood corpuscle},
          {white corpuscle}, {WBC}]