bonepill
A term used on 4chan's /lgbt/ board to refer to the information that one will not pass as the gender they identify as on account of their bone structure. Individual bonepills include comparisons between male and female Q angles, skull size measurements, ribcage measurements, and other sexually dimorphic skeletal features.
I was considering facial feminization surgery until I took the bonepill and realized that my skull was too large to ever pass as female.