Thanks all for adding to my trove of local expressions from both sides of the ocean. However ... except for what I took to be a facetious usage, I haven't gotten an answer for --- yonks.
I know it means years, but there are two things I want to know: is it ever used other than in "it's been yonks since...; would anyone (the Queen?) say "I can't believe I've reigned for so many yonks."? second, is it a class or gender thing? I picture it as a usage from the Belles of St. Trinians school girls or Sloane Rangers (are there still Sloane Rangers?) and never by men or boys or the missus at the chippie.
I'll wait patiently for illumination, for yonks if necessary.