Source : Webster's Revised Unabridged Dictionary (1913)

Parablast \Par"a*blast\, n. [Cf. Gr. ? to grow beside. See
   {Para-}, and {-blast}.] (Biol.)
   A portion of the mesoblast (of peripheral origin) of the
   developing embryo, the cells of which are especially
   concerned in forming the first blood and blood vessels. --C.
   S. Minot.