I'm reading a novel set in Dublin; many of the Irish terms I've figured out, such as semi d, and, while I believe I get the meaning of nixers from the context, I'd appreciate any enlightenment anyone could give me. Here's the sentence:
Half the Place was on the dole and all of them did nixers, specially when the beginning of the school year was coming up and the kids needed books and uniforms.

BTW, I know the term semi detached but don't really know what one looks like exactly.