一切經音義 9.278

9.278

垓刼（古文[多*(厂@火)]奒二形今作姟同古才反數名也風俗通曰十億曰兆十兆曰經十經曰姟姟猶大數之也）。

垓刼 [myriads of kalpas]: Ancient texts have the two forms [多*(厂@火)] and 奒; it is now written 姟, both [pronounced with the] fanqie 古才 (gāi). It is the name of a numerical unit. The Fengsu tong says: "Ten yis (ten million) make a zhao; ten zhaos make a jing; ten jings make a gai (姟)." 姟 represents an immense number.