The word is not attested elsewhere. The DMF lists a similar formation of pil- followed by an agent suffix: pileur, but this refers to the person whose occupation it is to grind or pound. The lexeme may be an error for pilun, attested in Continental French, but not in Anglo-Norman, cf. DMF pilon 1.
s.
1implementpestle, instrument for grinding or pounding ingredients into small fragments, a powder:
(
s.xiiiin; MS: s.xiiim
)
Se tu batz le fol sicum l’un bat tisane en une pile, e fierges adés sur lui od le pilur (Latin: Si contuderis stultum in pila quasi tipsanas feriente desuper pilo), ne lui tolderas tu sa folie
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