mid-sized store
Used in commercial contexts to describe a store that is neither a small shop nor a large department store.
This shopping street has many mid-sized stores and few large ones.
middle-class brothel (in a red-light district)
Historical term for a brothel of intermediate status in a red-light district, between high-class and low-class establishments.
In Edo-period Yoshiwara, middle-class brothels existed alongside high-class establishments.
Compound of 中 (middle) and 店 (store). The brothel sense is a historical extension of the 'mid-sized store' meaning.