kye, n.¹ — Green’s Dictionary of Slang

kye n.¹

[ety. unknown; Partridge (1984) suggests the Yid. kye, 18; but this is not cited in Rosen; note kibosh n. (3)]

one shilling and sixpence.

1873		Sl. Dict. 211: Kye eighteenpence.
1895		C. Crowe Aus. Sl. Dict. 43: Kye, eighteen-pence.
1937–84		Partridge DSUE (1984) 659: from ca. 1860.