What is a crab in the act of casting its shell, or immediately afterwards while still soft; -- applied especially to the edible crabs, which are most prized while in this state called?

shedder — (Zoöl.) A crab in the act of casting its shell, or immediately afterwards while still soft; -- applied especially to the edible crabs, which are most prized while in this state. (Webster's 1913.)

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