Not really the same as tetradecapod. It's the adjectival form.
I suggest that a tetradecapod is an animal with 40 legs, and tetradecapodous refers to an animal with 40 legs; viz. a tetradecapodous millipede. If there is such a thing.
I found this word while playing hangman against my computer. I wrote the program myself and I use a database that currently has 197,029 words. Since I guessed this word correctly, I can try to add another word.... looking at new words recently added to the OED, choose "channelopathy." It accepts that.