Definition of Quarantine:
Quarantine refers to a period of isolation or restriction imposed on individuals, animals, or things that may have been exposed to or infected with a contagious disease. It is a precautionary measure taken to prevent the spread of diseases.

Synonym of Quarantine:
The synonym of the word "quarantine" is Detention.

Explanation:
To understand why "detention" is the correct synonym for "quarantine," let's break down the meaning of both words.

Quarantine:
Quarantine involves isolating individuals, animals, or things for a specific period to prevent the spread of contagious diseases. It is typically implemented when there is a risk of transmission and aims to protect the larger population from potential infection. During quarantine, the movement and interactions of the quarantined subjects are restricted.

Detention:
Detention, on the other hand, refers to the act of keeping someone or something confined or restrained. It often involves holding individuals against their will for various reasons, such as punishment, protection, or investigation. In the context of disease control, detention can be used to prevent the spread of contagious illnesses by isolating potentially infected individuals or groups.

Similarities:
Both quarantine and detention involve the act of isolating and confining individuals or things for specific purposes. They share the common goal of preventing the spread of potential harm, whether it be contagious diseases or other risks.

Conclusion:
Considering the similarities in their meanings and purposes, "detention" serves as an appropriate synonym for "quarantine." Both words involve the act of isolating and confining to prevent harm or risks, making them interchangeable in certain contexts.