仮骨 is read as かこつ (kakotsu) and means callus.
かこつ
kakotsu
かめい
alias
かめん
mask
かりに
temporarily
たとい
even if
かてい
supposition
かそう
converted (cruiser)
かな
kana
かせつ
assumption
かりしょぶん
provisional disposition
hypothesis
かなづかい
kana orthography
imagination