Pycnodysostosis cuta ce ta kwayoyin halitta da ba kasafai ba wacce ke shafar ci gaban kashi kuma tana da gajeriyar tsayi, kasusuwa masu rauni, da rashin daidaituwa na kwanyar kai da kasusuwan fuska. Kalmar "pycnodysostosis" ta samo asali ne daga kalmomin Helenanci "pyknos" ma'ana "mai yawa
