Should spell it "do-hickey"?

[Jim McKee]

I mentioned to a friend that I had posted here about "doohickey", and
she suddenly remembered her mother, back in the 50's, referring to
certain unmentionables as "do-which-ies". I had speculated to my friend
that I was reminded also of a practice that came along about 30 years
ago of exclaiming "Do what?!" when "What did you say?" was really meant,
the exclamation being made in an exaggerated, comical way to convey
astonishment. I heard "Do what?!" on TV a lot back then.
It's also interesting that both by age-group and perhaps even general
speech custom, we seem to have very few "unmentionables" left.