Yeah it’s tricky.
I was struggling to come up with useful terms in that other thread, and decided on general synthesis ones for now (ADSR).
I was having a flip through Microsound yesterday to see if Roads had some generically useful name for these phases of sounds (for my use case), but nothing jumped out at me.
Transient, in particular, does have this very specific double use-case in the FluCoMa verse though. So perhaps some clear differentiation there would be useful.