Thirl

v.

(present participle thirling, simple past and past participle thirled)

  1. To pierce, perforate, penetrate
  2. (obsolete) To drill or bore

n.

  1. (archaic or dialectical) A hole, aperture, especially a nostril
  2. (dialectal) A low door in a dry-stone wall to allow sheep to pass through; a smoot

[The Daughter of Time — Josephine Tey]