Here’s an example of an unspecified adjective:
“Feel that special feeling.”
“Special?” How specifically is it special? Is that a good thing or a bad thing? Is it special because of it’s rarity? Are you saying “special” because it’s sinfully wonderful but you can’t say that? Especially with the unspecified noun that follows (a nominalization, actually), the speaker is leaving a LOT of room for interpretation.
Because it is unspecified, the speaker will not know exactly how the listener will interpret that sentence, but can be confident they will chose something special. In fact, if you’re doing a group induction everyone will feel something “special” and it might well be different for everyone, and yet they all feel as though you are talking directly to their experience.
Some other unspecified adjectives: (it is arguable that all adjectives are somewhat unspecific. Even if a person said “that was fantastic chile,” We wouldn’t really know exactly how good it was. Some adjectives are, however, more unspecified than others. Tonality will play a big role in the meaning communicated.)
fine (Melissa saw it in fine detail.) memorable (They had a memorable evening.) interesting (Helen had an interesting experience.) challenging (Joel had a challenging teacher.) fun (Annie sent a fun memo.)
You get the idea. Your being nonspecific does two things for you: 1. Your client will need to resolve the confusion that is engendered and 2. you will not be inadvertently speaking contrary to their experience.
Now go out there and practice with people. And have fun.