What is an abstract noun and how do you use it?

Abstract nouns are things that can't be experienced by the physical senses; they can't seen, heard, smelled, tasted, or touched; they are things that can only be known, understood, learned, believed, or felt emotionally.

There are some nouns that can be used as both an abstract or a concrete noun:

abstract: I don't get the point of that joke.

concrete: I've broken the point on my pencil.

abstract: We're going to visit Maggie to lift her spirits.

concrete: I have some spirits of camphor for that congestion.

abstract: I have the eight to midnight watch.

concrete: I received a new watch for my birthday.

abstract: I'm going to be a famous movie star.

concrete: That star near the horizon is the planet Venus.