Ninpo in Chinese / Japanese...

忍法 is Ninpo which can be translated as “Ninja Arts” from Japanese.

If you want this to mean “Ninja Arts,” you should consider this to be Japanese only. In Chinese, someone might read this as “patience law” or “the art of patience.”

The first character can be associated with “Ninja” since it is the “Nin” of “Ninja.” But the literal meaning is patience or perseverance. The second character means “law” or “method.” Often this is extended to mean or be translated as “arts.”

Within a Buddhist context (especially Chinese Buddhism), this is the method or stage of patience, the sixth of the seven stages of the Hīnayāna in the attainment of arhatship, or sainthood.