Webster's Revised Unabridged Dictionary (1913 + 1828)


Displaying 1 result(s) from the 1913 edition:
Acrania (Page: 16)

A*cra"ni*a (#), n. [NL., from Gr. priv. + skull.]

1. (Physiol.) Partial or total absence of the skull.

2. pl. (Zoöl.) The lowest group of Vertebrata, including the amphioxus, in which no skull exists.