1Lodging; a place to stay overnight such as an inn or temporary accommodation.
旅の途中で良い宿を見つけて、一晩ゆっくり休んだ。
On the trip I found a good inn and rested comfortably for one night.
冬は山小屋が唯一の宿になることがある。
In winter, a mountain hut can be the only available lodging.
2A relay station or post town; a place used historically (e.g., in the Edo period) as a staging point for travelers and goods.
五街道には数多くの宿が設けられ、旅人の往来を支えた。
Many post towns were established along the Five Routes to support travelers' passage.
その宿（宿場）は宿屋や馬継所が整っていた。
That post town had inns and horse relay stations well arranged.
3A mansion/constellation in Chinese astronomy; one of the Twenty-Eight Mansions used in traditional astrology/astronomy.
二十八宿の研究では、各宿（しゅく）が方位や吉凶と結び付けられる。
In studies of the Twenty-Eight Mansions, each mansion is associated with directions and auspiciousness or inauspiciousness.
暦の注釈にその日がどの宿に当たるかが示されている。
Calendar notes indicate which mansion corresponds to each day.