The Collaborative International Dictionary
Acorn-shell
Acorn-shell \A"corn-shell`\, n. (Zo["o]l.) One of the sessile cirripeds; a barnacle of the genus Balanus. See Barnacle.
Wiktionary
acorn-shell
n. One of the sessile cirripeds; a barnacle of the genus (taxlink Balanus genus noshow=1).
Usage examples of "acorn-shell".
Down came spiralling a few bits of bark and acorn-shell, quite in the old familiar way.