- Pro thyalosoma
- Pro thyalosoma Pro* thy`a*lo*so"ma, n.; pl. {Prothyalosomata}. [NL., fr. Gr. prw^tos first + "y`alos glass + ?, ?, body.] (Biol.) The investing portion, or spherical envelope, surrounding the eccentric germinal spot of the germinal vesicle. [1913 Webster]
The Collaborative International Dictionary of English. 2000.