what does abstract noun mean
Courage is an abstract noun because it cannot be seen, heard, tasted, touched, or smelled.
Even though noise can’t be touched—and the noise may even be coming from several places—you can hear the noise, so it’s a concrete noun.
One general way that you can tell the difference between the abstract and the concrete, is that you cannot touch something which is abstract. “Concrete”, like the building material of the same name, is, by definition, something you can touch. This is not an altogether satisfactory definition however. What about music? You can’t really touch music, can you? If it is very loud, or has a strong bass line or percussion, you might feel the sound waves, however. And you can certainly hear music. So “music” is not an abstract noun. It would be more accurate to say that abstract nouns cannot be experienced through the senses. “Smile” and “hug” are concrete nouns, but “love” and “friendship” are abstract nouns.
In English, an abstract noun is often a quality or attitude. “Happiness” is an example of an abstract noun that is a quality. “Careless” is an example of an abstract noun that is an attitude.