What is the meaning of “predicate” in this definition?

Question

I have trouble understanding the article on existence in this Philosophy dictionary.

Instantiation in reality, or actual being. Kant pointed out that existence is not a predicate.

What is the meaning of predicate in other words, put simply?

Answer 1

Predicate is a fact about some thing or person, e.g.:

I am tall

I am a man

I am going for a walk

tall, a man and going for a walk are predicates about me. But in

I exist

(according to Kant) exist isn't a predicate, because if I didn't exist there wouldn't be me to apply the predicate to. Cf.:

I don't exist

Here I isn't someone at all, while in:

I am not a man

I is someone about whom it is told that she is not a man.