[1] : The Collaborative International Dictionary of English v.0.48

mail \mail\, n. f. maille, of. also maaille, ll. medalia. see
   medal.
   1. a small piece of money; especially, an english silver
      half-penny of the time of henry v. obs. written also
      maile, and maille.
      1913 webster

   2. rent; tribute. obs., except in certain compounds and
      phrases, as blackmail, mails and duties, etc.
      1913 webster

   mail and duties scots law, the rents of an estate, in
      whatever form paid.
      1913 webster
see also:
medal maile maille mail and duties 

[2] : Bouvier's Law Dictionary, Revised 6th Ed (1856)

maile, ancient english law. a small piece of money; it also signified a 
rent, because the rent was paid with maile. 

Maile >> M Words
Maile, definition of term: Maile
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