The word somehow entered Polish-American speech via the Kashubian language or a tiny local dialect - how? It's just not plausible
I did not say that this was an actual route, just a possibility. But once you find one possible way, many others can be easily found. Just google "busia", in some intelligent way, and you will find many good examples.
Here are just few:
"cyga" mentioned Kramsko. I followed the tip:
Babimojszczyzna/ Ziemia Lubuska
babimojszczyzna.pl/index.php?option=com_content&view=articl e&id=63&Itemid=88
The dialect appears in Nowe Kramsko, Stare Kramsko, Wielkie Podmokla and Małe Podmokla.
Geographical and historical conditions have contributed to the isolation of the villages from other Polish lands and to the preservation of many archaisms. As a result of continuous contact with the people of Germany new words were also created, not found in other Polish regions.
busia - babciaNowe Kramsko, Stare Kramsko - Ziemia Lubuska
kramsko.pl.tl/Kramska-gwara.htm
busia - babciamuzeumkrajny.pl/content.php?cms_id=1193&sid=79c98d72baf1939 db5f57f618bdae9dc&kat=6&dzial=
(Krajna is situated in Northern Great Poland, north of Noteć River, between Gwda River on the West and Brda River on the East)
(All three rivers are good for kayaking. Gwda used to be a very clean river)
Muzeum Krajny - Mały słownik gwary Krajeńskiej
busia - babciadrawsko.freehost.pl/ok/30maja/Sandra/slownik.html
Wieleń Masurians - an ethnographic group of Polish people living in Noteć Forest, settled on the left bank of Noteć near Wieleń and Krzyż, as well as on the right bank of the Warta River near Wronki.
Tradition has it that their ancestors were brought from Masovia by Prince Piotr Sapieha in 1750s, to settle on the forest areas that had been ravaged by the cholera plague.
Included in this dictionary, are the words, expressions, phrases still in use by the older people from around Drawsko, Pęckowa and Piłki.
(Drawa and Stara Drawa Rivers are excellent kayaking areas)
Słownik gwary Mazurów Wieleńskich
busia - babciaAnd I am almost sure we could find many more examples, from some other areas of and near Great Poland. This covers quite a big area.
Now think about immigration patterns. Poor Galicia was one big source. But all the western and northern Poland was another. It was the Prussian policy to clean up many of those areas of indigenous Polish Population.
"In 1858, 76 Poles, (16 families) landed here by the Heinrich from Bremen. They had been told by a passage agent for the Bremen shipping interest, that they would receive 100 acres of land on going to Canada, free of any expense or pay. They sold their little cottages and few acres, and landed here paupers. They had not as much as the value of a loaf of bread in money amongst them. They said the agent at home had deceived them, in telling them the cost of removal from Prussian Poland to Quebec was a great deal less than they afterwards found out."ottawa.polemb.net/index.php?document=152
And to make things clear: I never claimed anything about "busia" being a literary world. All my recent posts were about dialects. Otherwise, delph, thanks for your quite sensible and reasonable comment. I wish your buddies learned how to be civil.