there are 'gypsies' -- a group of indian-sub continent people (based on language and DNA data) who used to be unsettled demi-artitians (and or demi theives) in most of eastern centeral europe. they like the jews, the homosexuals, the handicapped, were largely wiped out 60 some years ago. only a very small percentage of them still survive. they tend to have dark skin, and hair, and spoke their own language. there were never liked, and had the reputation of being theives and con artist.
a small percentage managed to move to western europe, and some retreated further east, and some ended up in US.
there are also travellers. travellers are mostly irish, (at least in US) and travellers are demi con men, and traders. they speak gaelic, with a specialized vocabulary, and they, too, are a semi nomadic people. (nowday living in RV's and/or mobil homes)
there are also tinkers. tinkers travelled (and were sometimes travellers, but tinkers mostly did small repairs on tin (and copper glaced tin) pot. they were also famous for 'lifting silver spoon' or other items from the kitchens they worked in.
(a) tinker is a noun, (to) tinker is a verb.
a tinker's dam (crossing thread!) is the small dam of putty a tinker would build round the hole in a pot before attempting to repair the pot with molten metal. when the solder (tin and lead!) was hard, the dam was knocked off. a tinkers dam is a fragile, temporary thing, of little use, made with cheap material, and not expected to last more than a few minutes--or, at least, thats how it started. nowdays, a tinkers dam is anything that is short lived, and generally worthless!
(authority for all this? NONE! but tinker's dam did come up before, and i know a little about travellers, and gypsies from general reading. gypsies got there name because they were supposed to have come from eygpt. (In england they were called the 'Romany', because they were thought to come from Romania, or to be 'left over' ancient romans)but post WWII studies of the surviving gypsies indicate their language was closer to language of the indian sub continent (i forget which, not a big one that i knew of).
of the 10 million killed in the death camps, over 6 million were jews. gypsies were the next biggest 'ethnic' group. their life style didn't create any great culture, and they don't have educated articulate spokesmens to tell their story.)