Green’s Dictionary of Slang

(Aus.) a semi-erect penis.

1998		Alex Chomicz [film title] Half Mongrel.
2001		Weekend Australian Mag. (Sydney) 2 June Features 17: ‘I don’t think this guy would sell many magazines,’ says the editor of Australian Women’s Forum, Helen Vnuk. ‘He’s a bit old for us and not really buff enough, and that hair is so early 1990s Michael Bolton. Also, his dick is looking a bit limp. We prefer semi-engorged (I think the technical term is a half mongrel).’.