* Integrity: This refers to the quality of being honest and having strong moral principles.
* Matron: While it can refer to a woman, it can also be used as an abstract noun to describe the qualities associated with a matronly figure like wisdom, experience, and nurturing.
The other words are concrete nouns:
* Mammoth: Refers to a specific animal.
* Marauder: Refers to a person who robs or attacks others.
Let me know if you'd like to explore abstract nouns further!