morts dock, n. — Green’s Dictionary of Slang

morts dock n.

[rhy. sl. proper name Morts Dock (Sydney Harbor) = cock n.³ (1)]

(Aus.) the penis.

1966		S.J. Baker Aus. Lang. (2 edn) 363: Mort's Dock, penis. Rhyme on cock. (Localized to Sydney).
1983		J. Byrell (con. 1959) Up the Cross 16: ‘Maybe flick a bit of talc around his morts dock and orchestra stalls, eh?’.
1997		R.G. Barrett Do What Do You Reckon? [ebook] And they’re all shaking hands and posing like this mort’s dock with ears had accomplished some great feat of daring.
2009		G. Seal Dog’s Eye & Dead Horse 118: Mort’s Dock - cock, meaning penis. Sometimes abbreviated to Morts. Historic Sydney shipbuilding site. World War II.
2015		businessballs.com 20 Apr. 🌐 Mort's dock - cock (penis - Mort's dock was a shipping berth in Sydney harbour for loading export wool from the major wool dealers Elders, Smith, Goldsborough, Mort Ltd).