Green’s Dictionary of Slang

skilly n.2

[? SE silly (girl)]

a (young) woman.

[UK][perf. Vesta Tilley] Sidney’s in civvies again 🎵 Sidney's in civvies again. Sidney's home once more / [...] / But he loves the skillies on the seaside Prom / [...] / He squeezes a little girlie in his dugout by the sea.