foulder

from The Collaborative International Dictionary of English v.0.48

Foulder \Foul"der\, v. i. [OE. fouldre lightning, fr. F. foudre,
   OF. also fouldre, fr. L. fulgur. See {Fulgor}.]
   To flash, as lightning; to lighten; to gleam; to thunder.
   [Obs.] "Flames of fouldering heat." --Spenser.
   [1913 Webster]