老中 (roju) refers to a historical title used during the Edo period in Japan. The term translates to "Elder" or "Senior Councilor" and was an important position within the Tokugawa shogunate's government. The roju were senior officials who advised the shogun and played a key role in the administration and governance of the country.

The roju had various responsibilities, including overseeing domestic affairs, managing foreign relations, and handling significant policy decisions. They were part of a council that made collective decisions on important matters. This position was usually held by daimyo (feudal lords) of significant standing and influence.

The number of roju varied over time, but there were typically four to five individuals holding this title simultaneously. Their influence and power were considerable, making them some of the most prominent figures in the Tokugawa shogunate.

介護 4 (kaigo 4) refers to a specific level of nursing care or assistance needed under Japan's Long-Term Care Insurance system. The system classifies the care needs of elderly individuals into seven levels: from 要支援1 (Yoshien 1, support level 1) to 要介護5 (Yokaigo 5, care level 5).

Kaigo 4 indicates a high level of care requirement, just one step below the most intensive care level, kaigo 5. Individuals assessed as needing kaigo 4 typically require significant assistance with daily activities such as bathing, dressing, eating, and mobility. They might also need extensive support for cognitive impairments or medical care.

The classification is determined through an assessment by municipal officials, who evaluate the individual's physical and mental health, and their ability to perform daily activities. Based on this assessment, appropriate care services are provided to meet their needs.

孫 (mago) means "grandchild" in English. It refers to the child of one's son or daughter. In Japanese culture, the term is used similarly to how it is used in English-speaking contexts, denoting a familial relationship across generations.

該当 (gaito) means "relevant," "applicable," or "corresponding" in English. It is used to describe something that fits or matches certain conditions, criteria, or situations.

所在 (shozai) refers to the "whereabouts," "location," or "place" of something or someone. It indicates the specific place where an object or person is located or can be found. This term is commonly used in both everyday and formal contexts to describe the position or location of various entities.

上京 (jokyo) refers to the act of going to the capital city, specifically Tokyo. Historically, it meant traveling to Kyoto, which was the capital of Japan until the Meiji Restoration in the late 19th century. Today, it commonly means moving to or visiting Tokyo, the current capital. This term is often used when people from other regions of Japan relocate to Tokyo for work, study, or other reasons.