Also spelled foilliu (obsolete). "Multure, a small proportion (legally one twenty-fourth) of each customer's grain which was retained by the miller instead of a money payment for grinding. From the correct Manx form of the word, fooillagh, leavings, remainder, it would appear that originally a miller's recompense was limited to the pollard and coarse bran. We may feel sure, however, that the term was not applied in that sense to the Lord's multure, as specified in the Earl of Derby's 'Orders and Directions' of 1636 (Statutes)."
—W. Walter Gill, Manx Dialect Words and Phrases, 1934, online here