Not

Not as a pet name is simply the English word used in negation, applied here as a name with a wry, humorous spirit. Pet owners sometimes choose ironic or unconventional names as a form of personality expression — naming a notably mischievous or unpredictable companion something that plays against expectations. The name is a conversation starter by design.

Not ranks #117 among the most popular pet names in America, which is remarkable for a word that is not a name at all in any traditional sense. This is the kind of name that tells you something about the owner — someone with a sense of humor, someone who wanted a companion with a name that would make people do a double take. It works especially well for pets with a rebellious streak or a habit of doing exactly what you asked them not to. There is a whole community of owners who delight in the absurdist charm of it.