Green’s Dictionary of Slang

St Nicholas’s clergyman n.

a highwayman.

1589		R. Harvey Plaine Percivall in Farmer & Henley Sl. and Its Analogues VI (1902) 35/2: A quarrel, by the highway side, between a brace of Saint Nicholas Clargie men .
c.1597		Shakespeare Henry IV Pt 1 I i: Sirrah, if they meet not with Saint Nicholas’ clerks, I’ll give thee this neck.
1633		Rowley Match at Midnight IV i: Hee’s a Knight abounding in deeds of charity, his name Sir Nicholas Nemo.
1663		J. Wilson Cheats I i: I was t’other night upon the randan, and who should I meet with but our old gang, some of St. Nicholas’ clerks.