the GNU version of the Collaborative International Dictionary of English
n. A loin of beef, or the upper part of the loin. See sirloin, the more usual, but not etymologically preferable, orthography.
The Century Dictionary and Cyclopedia
n. See sirloin.
Word Usage
"It is, perhaps, a pity to spoil so noble a story; but the interests of truth demand that we declare that sirloin is probably a corruption of surloin, which signifies the upper part of a loin, the prefix sur being equivalent to over or above."