dodman

from The Century Dictionary.

• noun An animal that casts its shell, like the lobster and crab.
• noun A shell-snail.

from the GNU version of the Collaborative International Dictionary of English.

• noun Obs. or Prov. Eng. A snail; also, a snail shell; a hodmandod.
• noun (Zoöl.), Prov. Eng. Any shellfish which casts its shell, as a lobster.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun UK, dialect A snail.
• noun UK, dialect A snail's shell.
• noun UK, dialect Any shellfish which casts its shell, such as a lobster.