ETYMOLOGY
apparently from clapper (the tongue of a bell) + dudgeon (hilt of a dagger):
the origin of the appellation is unknown.
John P. Collier (writer and scholar) suggests ‘from his knocking the clapdish (which beggars carried) with a knife or dudgeon’.
EXAMPLE
“… A pallyarde
These Palliards be called also Clapperdogens, these go with patched clokes, & haue their Morts with them, which they cal wiues and if he goe to one house to aske his almes, his wife shal goe to another, for what they get, as bread, cheese, malte, and well, they sel the same for redy money, for so they get more, and if they went together, although they be this deuided in the daie, yet they mete iompe at night. …”
From: A Caueat for Commen Cursetors vvlgarely called uagabones
By Thomas Harman, 1567
Lexicophilia 