Thanks Jdraw,
Following the tektips link, this can this be done then by appending a new property to the query definition(?), and assigning the new description to it.
Presumably, I can update the new property as and when(?).
I'm writing a large number of SQL queries in VBA, on the basis of differing hospital patient types and varying date intervals, and assigning the SQL strings to a query, but I wanted to update the query "description" as well, so I can keep track in the navigation pane of which queries do what.
Must admit with my little knowledge, I thought it would still be a doddle.