from Wiktionary, Creative Commons Attribution/Share-Alike License
- adj. Resembling an acorn; applied to a group of barnacles with shells shaped like acorns.
from the GNU version of the Collaborative International Dictionary of English
- adj. Resembling an acorn; -- applied to a group of barnacles having shells shaped like acorns. See acornshell, and barnacle.
from The Century Dictionary and Cyclopedia
- Resembling an acorn: specifically applied to the acorn-shells of the family Balanidæ. See cut under Balanus.
- n. An acorn-shell; a cirriped of the family Balanidæ.
Ancient Greek acorn + -oid. (Wiktionary)