kouji

Kouji, often written Koji or Kōji in English, is a Japanese term that can refer to a personal name as well as several other concepts. As a masculine given name, Koji is common in Japan, and its meaning depends on the kanji used to write it. Because there are many possible character combinations, there is no single universal meaning for the name.

In addition to being a given name, Koji also refers to a fermentation culture in East Asia. Koji (麹) denotes a mold, specifically Aspergillus oryzae, used to saccharify starches and enzymes in the production of foods and beverages. Koji is central to making sake, miso, soy sauce, and many other traditional ferments, and it is cultivated on grains such as rice or barley.

The term kouji can also appear in Japanese as 工事, which is read kōji and means construction work, a construction project, or civil engineering activity. This usage is distinct from the name or the fermentation mold and is a common everyday term in business, architecture, and urban development.

Kouji/Koji also appears in fiction and popular culture as a personal name for characters in books, films, and video games. The versatility of the term reflects its multiple origins in Japanese language and culture, spanning personal naming, culinary fermentation, and everyday vocabulary.