English Computing Dictionary
topic drift
Term used on GEnie, {Usenet} and other electronic
fora to describe the tendency of a {thread} to drift away from
the original subject of discussion (and thus, from the Subject
header of the originating message), or the results of that
Often used in gentle reminders that the discussion has strayed
off any useful track. "I think we started with a question
about Niven's last book, but we've ended up discussing the
sexual habits of the common marmoset. Now ▫that's▫ topic
[{Jargon File}]