The Collaborative International Dictionary
Thirling
Thirl \Thirl\, v. t. [imp. & p. p. Thirled; p. pr. & vb. n. Thirling.] [See Thrill.] To bore; to drill or thrill. See Thrill. [Obs. or Prov.]
That with a spear was thirled his breast bone.
--Chaucer.
Wiktionary
thirling
vb. (present participle of thirl English)