A dodman (plural "dodmen") or a hoddyman dod is a local English vernacular word for a land snail.
[1] Alternatively (and apparently now more commonly used in the Norfolk dialect) are the closely related words Dodderman or Doddiman.
"[2]The 'inventor' of ley lines, Alfred Watkins, thought that in the words "dodman" and the builder's "hod" there was a survival of an ancient British term for a surveyor.
Watkins felt that the name came about because the snail's two horns resembled a surveyor's two surveying rods.
Watkins also supported this idea with an etymology from 'doddering along' and 'dodge' (akin, in his mind, to the series of actions a surveyor would carry out in moving his rod back and forth until it accurately lined up with another one as a backsight or foresight) and the Welsh verb 'dodi' meaning to lay or place.