variante(s): biro, biron, viro

n. m.

'vrille, foret'

D: 1271 ⊂ DocMillau₂A 16,24 (biro); 1524 ⊂ Pans₅ (b‑); LRaisDV 28,32 (‑o)

FEW 14:388a [ᴠɪ̄ʙʀᴀʀᴇ].