When the fore skin of a males penis is half cut off, in turn making it look line a ninja mask.

Or
The legendary staff that only the most trained and skilled ninjas acquire.
"Look at Jimmy's penis! He's got a Ninjeyrod!"
Or
"Master am I ready?"
"Yes my son you are now the highest of ranking, here is your Ninjeyrod"
by PeenSnatcher69 April 2, 2019
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