Source : Webster's Revised Unabridged Dictionary (1913)

Emboil \Em*boil"\, v. i.
   To boil with anger; to effervesce. [Obs.] --Spenser.

Emboil \Em*boil"\, v. t.
   To cause to boil with anger; to irritate; to chafe. [Obs.]
   --Spenser.