dago T n. a ribbed, white cotton tank-style undershirt; a wife-beater; a boy-beater. Editorial Note: A synonym is guinea T, which, like dago T, is often perceived as derogatory or offensive. (source: Double-Tongued Dictionary)
Further reading
Sure, there’s winter, spring, summer, and fall. But the seasons in between have even more poetic names. In Alaska, greenup describes a sudden, dramatic burst of green after a long, dark winter. And there are many, many terms for a cold snap...
Centuries ago, monks who took a vow of silence developed their own hand signs, with hundreds of gestures, that are still in use today. Plus, how do speakers of different languages distinguish similar shades and tints of colors such as red, yellow...
Found a new instance to add to definition, used as ‘obscene slang’ against a Mr.E :
“That’s what E is—a DAGO!”
He nodded like a man who gives a last tap to a nail, and I could see he considered his remark well and truly laid.
~ H.G.Wells in Tono-Bungay, 1909