If you want to see those related to real life ninjutsu, you can always check this web
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Now, if you want to know the meaning in Narutoverse, you might be looking for this
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...which are the animals of the Chinese calendar. Kishimoto adapted the concept of
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, disguised with these signs.
...in which case, Madara is performing a one-handed Ram/Goat.
Edit:
The Kuji-in is a reference that should pick the attention of the users here, since even if the chinese animal are the traditional hand seals used in Narutoverse, most of the special handseals used belongs to the Kuji-in repertory.
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For instance,
the Zai is used by Minato when using his Time-space vortex barrier technique.
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The Toh is used by Gai when using Hirudora
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The Kai is used by Yamato/Hashirama when using Wood Style
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...and finally (but not least important), the Retsu (which is the Rat sign in the Chinese calendar previously posted) was used by Sasuke and Naruto to free people from IT (they restored the time-space which was being distorted by the Infinite Tsukiyomi, provoking dreams on the people).
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