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1. Having, resembling, or constituting a hard crust or shell.
2. Crustacean.

[Latin crūsta, shell; see kreus- in Indo-European roots + -aceous.]


1. forming, resembling, or possessing a surrounding crust or shell
2. (Animals) zoology another word for crustacean2


(krʌˈsteɪ ʃəs)

1. of the nature of or pertaining to a crust or shell.
3. having a hard covering or crust.
[1640–50; < New Latin crūstāceus (adj.) hard-shelled. See crustacean, -aceous]
ThesaurusAntonymsRelated WordsSynonymsLegend:
Adj.1.crustaceous - of or belonging to the class Crustacea
2.crustaceous - being or having or resembling a hard crust or shell
References in classic literature ?
A minute crustaceous animal (Cancer salinus) is said [4] to live in countless numbers in the brine-pans at Lymington: but only in those in which the fluid has attained, from evaporation, considerable strength -- namely, about a quarter of a pound of salt to a pint of water.
The Siberian salt-lakes are inhabited by small crustaceous animals; and flamingoes (Edin.
The main signs and symptoms are a crustaceous lesion (early) or eschar (late) at the site of the tick's attachment and regional painful lymph nodes (10,11).
This crustaceous endeavor's ending date depends on the season and ice; some years they can't finish until late May.
Many of the fossils come from the Yixian Formation, which is believed to date from the Late Jurassic-Early Crustaceous period.