Meanings
- obsoletepluralplural onlybiologyAny of various shellfish, especially those of the obsolete orders Vermes or Acephala, or the suborder Thecosomata.
The echinite family […] may be deemed characteristic of the chalk formation, affording of itself as many shells as the other testacea do.
1829, Andrew Ure, A New System of Geology, page 2852 more examples
ANAIMONA, Aquatilia Exanguia, Bloodless Fishes, are divided into Mollia Soft Fishes without Shells; Crustata, those that are covered with thin pliant Shells; and Testacea, those which have thick, hard brittle Shells.
1722, John Jones (tr.), Oppian's Halieuticks of the Nature of Fishes and Fishing of the Ancients, page 231[…]to fancy, for example, that the testacea of the ocean existed first, until some of them, by gradual evolution, were improved into those inhabiting the land.
1832, Charles Lyell, chapter I, in Principles of Geology […] , volume II, London: John Murray, page 11
- obsoleterareuncountableA testaceous substance, something made of shell or shell-like material.
Origin
- Latintestāceus“covered with a shell”
- Englishtestacea
From Latin testāceus (“covered with a shell”).
More words from Latin
Full word history & related roots →Cite this entry
testacea. (n.d.). In WatkinsX Dictionary. Retrieved November 3, 2026, from https://dictionary.watkinsx.com/word/testacea
“testacea.” WatkinsX Dictionary, https://dictionary.watkinsx.com/word/testacea. Accessed November 3, 2026.
WatkinsX Dictionary, s.v. “testacea,” accessed November 3, 2026, https://dictionary.watkinsx.com/word/testacea.
Source: testacea on Wiktionary, CC BY-SA 4.0.