Synonyms for Crawfish (same or very similar meaning)
WordNet sense 1 (tiny lobster-like crustaceans usually boiled briefly):
crawdad, crayfish, ecrevisse
WordNet sense 2 (small freshwater decapod crustacean that resembles a lobster):
crawdaddy
WordNet sense 3 (large edible marine crustacean having a spiny carapace but lacking the large pincers of true lobsters):
langouste, spiny lobster, rock lobster, sea crawfish
WordNet sense 4 (make a retreat from an earlier commitment or activity):
retreat, withdraw, back out, pull back, back away, crawfish out, pull in one's horns
From the ODE community, based on WordNet
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