Green’s Dictionary of Slang

a negative intensifier, lit. ‘syphilitically’.

1600		Weakest goeth to the Wall line 250: These French mens feete haue a pockie strong sent.
1608		Dekker Lanthorne and Candle-Light Ch. 9: Are they so dry in the Suburbs? Yes: pockily dry.
1618		Owles almanacke 10: Scorpio, the Scorpion, gouernes the secret parts, for those sting pockily.
1663		Head Hic et Ubique V iv: Why, thou art ham-shrunk, and broken-winded too. Don’t thy bones ache pockily?