A "Sage" (仙人, Sennin) is someone who is able to utilise senjutsu (仙術, Literally meaning: Sage Techniques), and has mastered the art of Sage Mode or someone given said title because of their renown for their great power, wisdom, or holy standing.
Main articles: Senjutsu and Sage Mode Senjutsu (仙術, English TV: Sage Jutsu, Literally meaning: Sage Techniques) refers to a specialised field of techniques that allows the user to sense and then gather the natural energy (自然エネルギー, shizen enerugī) around a person.
Main articles: Sage Mode, Sage Transformation and Orochimaru's Juinjutsu Senjutsu practitioners learn to draw the energy of nature inside of them, blending it with their own chakra (created from spiritual and physical energy within the shinobi). This adds a new dimension of power to the practitioner's chakra, resulting in the creation of "senjutsu chakra" (仙術チャクラ, senjutsu chakura). In humans, this new chakra enables the user to enter an empowered state called Sage Mode. Those that can absorb or manipulate senjutsu chakra are known as sages (仙人, sennin). Currently, there are two known ways to learn senjutsu: One being to learn from the toads of Mount Myōboku as Jiraiya, Minato and Naruto have done, and the other from the snakes from the Ryūchi Cave where Orochimaru and Kabuto Yakushi learned it. Very few people are shown to have mastered senjutsu. This is because both learning and using senjutsu is not safe; death may easily occur while learning to use it. Fukasaku claims that the toad sculptures on Mount Myōboku are those who failed to master the art of senjutsu. Naruto Uzumaki, Kabuto Yakushi, Hashirama Senju, Orochimaru and Jiraiya are currently the only known human users of senjutsu. Other animals such as Fukasaku and Shima are also able to use it with the White Snake Sage and Great Toad Sage amongst others, being at least knowledgeable in it.
"Sage" can also refer to an individual renowned for their great power, wisdom, or holy standing.
- Hagoromo Ōtsutsuki, the original Sage of Six Paths, was one of the most famous sages in the series, a legendary figure who discovered chakra, created modern ninjutsu, the one who saved the world from the Shinju and was the first jinchūriki. As the first jinchūriki of the Shinju, he was able to use natural energy in his techniques, just as the current one, Obito Uchiha, is capable of doing. However, it is uncertain whether Hagoromo was able to use senjutsu before he sealed the beast within himself.
- Son Gokū's moniker: The Great Sage Equalling Heaven (斉天大聖, Seiten Taisei) also makes mention of being a Sage.
- The term 仙人 (Sennin), refers to the Japanese term of Chinese sages and practitioners of Taoist ways, who have gained immortality and incredible powers through the manipulation of qi, or natural energy through their body by becoming ascetics and living on mountains, where qi is said to gather at the most and to start flowing from into the world. The training and measures needed to become a Sage in Naruto is just as vigorous and demanding, and similar in some regards, requiring one to have massive reserves of chakra, and come to adopt natural energy, not for the pursuit of immortality, but to become harmonised with the flow of the world around them.