Source : Webster's Revised Unabridged Dictionary (1913)

Embolism \Em"bo*lism\, n. [L. embolismus, from Gr. ? to throw or
   put in, insert; cf. ? intercalated: cf. F. embolisme. See
   {Emblem}.]
   1. Intercalation; the insertion of days, months, or years, in
      an account of time, to produce regularity; as, the
      embolism of a lunar month in the Greek year.

   2. Intercalated time. --Johnson.

   3. (Med.) The occlusion of a blood vessel by an embolus.
      Embolism in the brain often produces sudden
      unconsciousness and paralysis.

Source : WordNet®

embolism
     n 1: an insertion into a calendar [syn: {intercalation}]
     2: occlusion of a blood vessel by an embolus (a loose clot or
        air bubble or other particle)