I thought Dogecoin came from that cute dog that also had its own meme later on? It is based on an animal dog, hence it was also named as that but again without that letter 'I'.
The coin got its name from the meme, and the meme comes from a misspelling of the word dog. This misspelled word came from an episode of Homestar Runner, where one character calls another “my d-o-g-e” because he is too dumb to know how dog is spelled.