Bonular appears to be the correct spelling for that pronunciation. For example, in answerbag.com post #572879 (28 Jan 2008) Jodie44 wrote:
Bonular, pronounced BONE-u-lar. I’ve used it a bunch of times because it seems right. As in, “I went to the doctor thinking I had a muscular problem, but it ended up being bonular.”
With fewer than 800 google hits, bonular is rare enough that you probably can adopt it as a project name without high risk of conflict. However, I think the modular portion of your derivation does not survive being connected to bone (which might not matter, since you probably will have an explanatory paragraph for the name).