Necklace bone: transitive verb, or if accuracy is important to you, then it's a noun. The small round, holed bone sticking out from the back of the neck, reminiscent of the non-claspy catchy bit of a necklace - hence its name. It's covered with the thinnest skin anywhere on the human body and usually catches on a woman's The Thing With No Euphemism during childbirth and is ripped off. Many doctors deny its existence, but then again doctors used to say that the world was flat. Then again again, doctors used to say that water boils at 100șC, so rush to your own judgments.
I broke her necklace bone; I guess if I cared I'd feel guilty, but I don't so I won't. She asked me to help her put on her necklace (it was cheap and ugly) so I did. I removed the necklace bone-esque bit of the necklace, and replaced it with the spare claspy catchy necklace bit that I always carry around with me for just such an emergency. Picture the scene if you will: a necklace with two catchy claspy bits on. What is a guy to do but attach both of them to her necklace bone? Well, that was, after all, my plan all along: necklaces are tougher than skin, so the friction of her wearing it would gradually wear away at her neck. My way, the necklace bone would hold the necklace in place and her neck wouldn't be severed. You always see people with necks where their necklaces have worn away at the skin, and buried themselves deep by the bone and then had the skin grow over the top. Look around.
I suppose I'd better do that whole arthouse Pulp Fiction wrong chronology thing (forgetfulness and refusal to cut and paste) and explain why she had a necklace bone, running against the wolves of society. She was a test tube baby - c'est the only reason why necklace bones exist: for us to see who is a test tube baby and who isn't. The diameter of the test tube is 11cm, because glass is less forgiving than a woman's The Thing With No Euphemism. This extra centimetre keeps the necklace bone intact, at least until some clumsy oaf like me tries to help someone put on a necklace and not sever their neck, and then upon completion, catches a wrist hair on the necklace, leaving a necklace with two claspy catchy things and a necklace bone. If it was rare and valuable it'd be worth a lot of money, I'll bet.
Boy, was she mad. Well, not so much mad as severely mentally ill. So mentally ill in fact, that she didn't even notice that I'd broken her necklace bone clean orff and made her cheap and ugly necklace longer, and potentially valuable if ever there was a market for necklaces with two claspy catchy things and a necklace bone. One more time to improve the search engine rankings: two claspy catchy things and a necklace bone.