There isn't any! Latin doesn"t have words like ninja, Pizza, things like that where there aren't any in their state.
Latin is the language of the ancient Romans. Since ninjas are not part of ancient Roman culture there is no Latin word with that meaning.
Ninja in Portuguese is "ninja."
In Japanese "pink" is ピンク (pinku) and "ninja" is 忍者 (ninja), so to say "Pink ninja" it is ピンク忍者 (pinku ninja).
ninja firey
In French, "ninja" is translated as "ninja." It is the same word in both English and French.
tortues de ninja
Ninja = 忍者 (Rěnzhě)
"¿Te gusta Ninja Saga?"
黒忍者 Kuro ninja
you say helmet in latin (casco)<- in latin
忍者の虎 Ninja no tora
warui ninja Warui means bad or mean
If you really want to be, get a ninja guide on amazon. I can't say if you will or not. That is a choice.