from
The Collaborative International Dictionary of English v.0.48
Testaceous \Tes*ta"ceous\, a. [L. testaceus, fr. testa a shell.
See {Testa}.]
1. Of or pertaining to shells; consisted of a hard shell, or
having a hard shell.
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2. (Bot. & Zool.) Having a dull red brick color or a brownish
yellow color.
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{Testaceous animals} (Zool.), animals having a firm,
calcareous shell, as oysters and clams, thus distinguished
from {crustaceous animals}, whose shells are more thin and
soft, and consist of several joints, or articulations, as
lobsters and crabs.
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