Definition of megalosphere in English:

megalosphere

Pronunciation /ˈmɛɡələ(ʊ)sfɪə/ /ˈmɛɡ(ə)lə(ʊ)sfɪə/

noun

Zoology
  • The proloculus of a megalospheric foraminiferan shell.

Origin

Late 19th century. From megalo- + sphere, after French mégasphère.