What is "emboil"

Emboil \Em*boil"\, v. t. To cause to boil with anger; to irritate; to chafe. [Obs.]
--Spenser. [1913 Webster] ||

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

vb. 1 (context obsolete intransitive English) To boil with anger; to effervesce. 2 (context obsolete transitive English) To cause to boil with anger; to irritate; to chafe.