CETI or Ceti may refer to:
* Genitive word used to identify the stars belonging to the constellation
Cetus
Cetus () is a constellation, sometimes called 'the whale' in English. The Cetus (mythology), Cetus was a sea monster in Greek mythology which both Perseus and Heracles needed to slay. Cetus is in the region of the sky that contains other water- ...
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Communication with extraterrestrial intelligence
The communication with extraterrestrial intelligence (CETI) is a branch of the search for extraterrestrial intelligence (SETI) that focuses on composing and deciphering interstellar messages that theoretically could be understood by another techn ...
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Sicydium plumieri, Cetí'', a fish from Puerto Rico
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Project CETI
Project CETI is an international initiative to understand the acoustic communication of sperm whales using advances in artificial intelligence. The project has an interdisciplinary scientific board including marine biologists, artificial intelli ...
, an international initiative to understand the communication of sperm whales
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