Abstract Nouns

Abstract nouns are ideas, feelings or qualities such as love, hate, kindness, fear, anger, imagination, courage, intelligence, loneliness, happiness, sadness, bravery, cowardice, embarrassment, joy, beauty, ugliness, confidence, luck, misfortune, mischief, bitterness, justice, injustice, grief, boredom, cheerfulness.

More abstract nouns:

beauty
deceit
dedication
curiosity
trust
relaxation

Abstract nouns cannot be seen or touched in the same way as concrete nouns such as chair, table, dog, Lancaster, or Thomas.

An abstract noun refers to states, events, concepts, feelings, qualities, etc., that you can't touch.
eg: freedom; happiness; idea; music are all abstract nouns that you can't touch.

Here is an example:

When Pyewacket was confronted with a closed cupboard door, her curiosity got the best of her and she just had to find a way to open it!

Curiosity, one of the nouns in this sentence, is an example of an abstract noun. You cannot see curiosity itself. Curiosity has no color, size, shape, sound, odor, flavor, or texture; it has no quality that you can see, hear, smell, taste, or touch. Any noun that escapes your five senses is an abstract noun. So, you can't hear it, feel it, touch it, taste it or smell it.