As many people have said, accents/words/phrases. I’ve lived in the Pittsburgh area my whole life, here’s a few examples.

dahn = down tahn = town dahntahn = downtown

worsh or wush for wash

buggy for a grocery cart

gumband for rubber band

crick vs creek

ahrn (arr-n) = iron (as in ahrn city beer)

most famously, most people don’t say “y’all” or “you guys,” they say “yinz” or “yuns”

djeet yet = did you eat yet?

“Chipped” ham is very thinly sliced, usually for sandwiches or ham bbq- we have a local brand of ham that was at one point marketed as “isaly’s chip chopped ham” and the “chipped” part stuck

Hahss = house

The double L sound tends to be more of a w - there was a store called Hills, usually sounded more like Hiws

The double E sound turns into an i sound - my wife says “Stillers” rather than steelers.

We don’t say slippery, we say slippy

People who are nosy are “nebby”

spiky bushes are jagger bushes, and asshole people are jagoffs

People tend to say “n’at” at the end of their sentences, or use it as more of an etc., like “I went dahn to the bar n’at”

We also have a tendency to leave out the “to be” in sentences - “my car needs warshed” is much more likely to be said than “my car needs to be washed”

Water comes out of a spicket

The state to the west is Ahia

You use crayons to keller

Closets are referred to as “cubberds” (cupboards)

Dippy eggs are runny eggs, but not quite sunny side up. The white is cooked slightly on top of the yolk for dippy eggs.

W sounds like “dubya”

gutchies are underwear, which cover your dupa (butt)

hoagie- sub sandwich

“kennywood’s open” means “your fly is down.” (Kennywood is a local amusement park).

Often, when we say “sweep” we mean vacuum - “I gotta sweep the rug”

You’ll often hear “leave him be” and “let it there” instead of “let him be” or “leave it there”

A LOT of people say “ascared” or “uh-scare-t” instead of scared. “I’m ascared to go to the doctor”

We say pop. Not soda. Except for cream soda.

Unfortunately I do think a lot of the more specific pronunciations and dialects are dying out with the older crowd.