Source : Webster's Revised Unabridged Dictionary (1913)

Sebaceous \Se*ba"ceous\, a. [NL. sebaceus, from L. sebum tallow,
   grease.] (Physiol.)
   Pertaining to, or secreting, fat; composed of fat; having the
   appearance of fat; as, the sebaceous secretions of some
   plants, or the sebaceous humor of animals.

   {Sebaceous cyst} (Med.), a cyst formed by distention of a
      sebaceous gland, due to obstruction of its excretory duct.
      

   {Sebaceous glands} (Anat.), small subcutaneous glands,
      usually connected with hair follicles. They secrete an
      oily semifluid matter, composed in great part of fat,
      which softens and lubricates the hair and skin.

Source : WordNet®

sebaceous cyst
     n : a common cyst of the skin; filled with fatty matter (sebum)
         that is secreted by a sebaceous gland that has been
         blocked [syn: {pilar cyst}, {wen}, {steatocystoma}]