Predicates in NLP are words that connect to one of the five representational systems: visual, auditory, kinaesthetic, olfactory and gustatory. They are a reflection of those systems and they also give us clues to the representational system that someone is using.
For example if this makes perfect sense you might sense, “oh, I see what you mean”. That would be linked to the visual system.
On the other hand you might still be wondering what I’m talking about and say “it’s all Greek to me”… which would be auditory (what you can – or in this case cannot – here).
By this point you might find yourself saying “oh I’m starting to get a handle on it now” which might suggest… that’s right, a kinaesthetic preference.
It can be fun to watch out for the predicates that you and other people are using (yes, that was me being visual). It’s another way to improve communication with other people (and your self!)