"yer ma" is a generic response when you can't think of anything else to say. Mostly used in Scotland, and by yer ma (see...)

Yer ma is an insult often used by "mokes", "steeks", "spides" and "millies".

Basically it means your mother, often return firing an insult, or saying I had (slept) with your mother.

Return fire with something like "You did mate.. I would seriously consider visiting a doctor about that, coulda caught something" "What would you rate her? 8 out of 10? She's good isn't she?" "My "You dug her up from the ground you sick bastard?!" "She's dead" (I hate this one..) "She's had a lot of people you know."

A crappy inslut that has been said to me 100's of thimes when I clamp chavs and they have nothing to say. Chavs are the scum of Scotland, neigh...the WORLD!

All of these definition's say its either from Scotland or Northern Ireland but thats bullshit its from Dublin.
"Yer Ma" Is a phrase used as a comeback to ANYTHING.
It can be a part of a long insult(Ex.1) or just used as itself.(Ex. 2)

a northern irish version of "ya mum".
The normal reply to it would be "aye, yer's ma's ma"
or "smell yer ma"
mind you, the conversation ( if you could call it that) could also start with smell yer ma, depending on what mood you're in.

A comeback Insult used by High school Kids in Scotland.

You heard me
Only used in AVA

TCW