In a recent edition of the Shonen Jump, Kubo Tite revealed his method for naming the arrancar. It would appear that his names are inspired by his other career of interest. Take a look:

"This isn't something I normally do, but I got the idea of the Arrancar names from those of architects and designers. There is, in fact, a furniture designer named Ulquiiorra. And Grimmjow is inspired by an architect named Niicholas Grimshaw."

Now, as for why he picked "jow" instead of "shaw" is an entirely different question to which we may never know the answer. (My guess is that he picked it because it sounds menacing...after all, it would match his character.)

 

 

 

 

 

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