Explanation:
Cleanliness is next to godliness is a popular saying that emphasizes the importance of cleanliness in our lives. In this sentence, the underlined word "cleanliness" is a noun. Nouns are words that represent people, places, things, or ideas. They can be classified into different categories based on their characteristics. In this case, the noun "cleanliness" is an abstract noun.

Abstract Nouns:
Abstract nouns are nouns that represent ideas, concepts, qualities, or states that cannot be perceived by the five senses. They are things that we cannot see, hear, touch, taste, or smell. Examples of abstract nouns include love, happiness, honesty, bravery, and cleanliness.

Importance of Cleanliness:
Cleanliness refers to the state of being clean or free from dirt, germs, or impurities. It is an important aspect of our daily lives as it helps to maintain good health and prevent the spread of diseases. Cleanliness also plays a crucial role in creating a pleasant and hygienic environment.

Comparing Cleanliness to Godliness:
The saying "Cleanliness is next to godliness" implies that cleanliness is highly valued and is closely associated with spiritual purity and moral goodness. It suggests that maintaining cleanliness in our physical surroundings and personal hygiene is a reflection of our character and righteousness.

Conclusion:
In conclusion, the noun "cleanliness" in the sentence "Cleanliness is next to godliness" is an abstract noun. Abstract nouns represent ideas, concepts, qualities, or states that cannot be perceived by the five senses. Cleanliness is an important aspect of our lives and is associated with spiritual purity and moral goodness.