This term first appeared in the late 1900s and can be attributed to Pinkerton Detective Agency, which was known for tracking down funds stolen from county Post Offices.  The term "Yegg". or "Yegg man" is most likely derived from John Yegg, the alias of a bank robber who was active during the late 19th and early 20th centuries.  The term yeggman was first used by the Golden Valley Chronicle in the early 20th century to refer a criminal, usually a burglar or a safecracker. 

In Scotland a safe cracker was called a Peterman, a term which was believed to have arisen from Peterhead, a jail in Aberdeenshire that housed many different safe-burglars during its time in use.   

10 hours ago, sandrewn said:

I am not finished yet, but one site, Merriam-Webster, has an entry on it, as part of an interesting list of 11 obscure word for thieves:

11 Obscure Words for Thieves | Merriam-Webster

 

And the search continues,

Imagine someone calling out: "Why, that no good freefootin' pennyweightin' footpad!"

As much as I was enjoying snooping around for more stuff on, the Word of the Day. After finding a reference to used condoms(that I would rather/will not talk about) the time had come to quit. I found a way to end this on a lighter note, with  two; Merrie Melodies shorts. The funnier one, in my opinion, is, Daffy Duck in "Golden Yeggs" from 1950, but is not free(sorry).

Golden Yeggs - Wikipedia

The second one, Bugs Bunny in "Easter Yeggs" from 1947. It was my first time seeing it, hope you enjoy it as well.

Robert McKimson’s “Easter Yeggs” (1947) Starring Bugs Bunny |

(scroll down, then click on the cartoon)

"That's all Folks!" ,