Ninpo Taijutsu is this
Japanese martial art's current correct name, this can be broken into
nin: Hidden
po: art
Tai: Body
Jutsu: Movement
so quite literally it means the hidden art of/in body movement. It's current soke is Dr Hatsumi Masaaki which is sometimes written as Masaaki Hatusmi.
Ninjutsu can be broken into just "hidden movement"
These translations are very loose since the Japanese language is so alien in comparison to Western languages.
Ninjutsu is actually 9 schools of martial art.
1. Togakure Ryu Ninpo Taijutsu
2. Gyokko Ryu Kosshijutsu
3. Kukishinden Ryu Happo Hikeniutsu
4. Koto Ryu Koppojutsu
5. Shindenfudo Ryu Dakentaijutsu
6. Takagi Yoshin Ryu Jutaijutsu
7. Gikan Ryu Koppojutusu
8. Gyokkushin Ryu Ninjutsu
9. Kumogakure Ryu Ninjutsu
The last known practitioner that faced open battle was Takamatsu Toshitsugu