The Collaborative International Dictionary of English v.0.48:

Prester \Pres"ter\, n. [NL., fr. Gr. ?, from ? to kindle or
   burn, and ? to blow up, swell out by blowing.]
   1. A meteor or exhalation formerly supposed to be thrown from
      the clouds with such violence that by collision it is set
      on fire. [Obs.]
      [1913 Webster]

   2. pl. One of the veins of the neck when swollen with anger
      or other excitement. [Obs.]
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Prester \Pres"ter\, n. [OF. prestre. See Priest.]
   A priest or presbyter; as, Prester John. [Obs.]
   [1913 Webster]