Oh, that is very frustrating. Sorry Dianna.
I tend to define HyFlex every time I use the word. This week I am doing some training sessions for fellow faculty on the classroom equipment we installed to support HyFlex. Your post reminded me to include the definition of HyFlex in the presentation (I actually do it twice – once at the beginning and once at the end).
Helping peers with the definition is easier than helping administrators though, as we may not see them as often. Perhaps including the definition of HyFlex and linking to sources in grant proposals could help? I would not have thought to do so for grants targeting “HyFlex” but your experience shows it is not yet universally understood.