Tenzin is a character in The Legend of Korra, The upcoming spinoff of Avatar: The Last Airbender. He is the son of Aang and Katara, two main characters from the original show.
The character Tenzing Tharkay from Naomi Novik's Temeraire series of books bears a variant of this name; he's an adventurer of Nepali and English descent who first appears in the book Black Powder War.