Where does “oquedad” come from?

oquedad (Spanish) comes from Spanish hueco, from Old Spanish ocar, from Czech oko, from Old Czech oko, from Proto-Slavic ȍko, from Proto-Balto-Slavic ak-, from Proto-Indo-European h₃ókʷs, from Proto-Indo-European h₃ekʷ- — to see; eye.

oquedad (Spanish): hollow, hollow space, cavity, hole;...