Adjunct mostly just means "collaborating with us", it's not a term of derision. If he got a fancier title they'd probably have to commit to more interaction, a

Adjunct mostly just means "collaborating with us", it's not a term of derision. If he got a fancier title they'd probably have to commit to more interaction, and heavier obligations, as would he. (And not a single soul at 80 years old is likely to want to take on some committee service for a university program...)