Monmouth street cut, n. — Green’s Dictionary of Slang

Monmouth street cut n.

[the reputation of London’s Monmouth Street, Covent Garden, as the centre of the second-hand clothes trade]

a garment that is too big for its wearer.

1825

Pierce Egan’s Life in London 11 Sept. 261/3: His dress had been the same for half a century—namely, a coat, with a broad back and long waist ‘of the Monmouth -street cut,’ that is, much too large for his body.