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

dunga n.¹

also dunger

[? ‘combining “donger” and “punga”, the tree fern with the suggestive penis shape’ (McGill, Dict. of Kiwi Sl., 1988)]

(N.Z.)

1. the penis.

1988		McGill Dict. of Kiwi Sl. 41/1: dunga [...] penis, perhaps combining ‘donger’ and ‘punga’, the tree fern with the suggestive penis shape.
2003		McGill Reed Dict. of N.Z. Sl. 64: donger/dunga/dunger 1. The penis, variants of British dong.

2. a general term of abuse.

2003

McGill Reed Dict. of N.Z. Sl. 64: donger/dunga/dunger [...] 2. An idiot.