- The geographic region between 10 degrees north and 40 degrees north latitude, especially when considered as a target for missionary work.
- 1995, George Otis & Mark Brockman, Strongholds of the 10/40 window, →ISBN:
- This intercessor's guide features maps and information on each 10/40 Window nation, covering trends, religions, people groups, and history.
- 1996, Gailyn Van Rheenen, Missions: Biblical Foundations and Contemporary Strategies, →ISBN, page 209:
- All three major non-Christian religions — Islam, Hinduism, and Buddhism — originated in the 10/40 Window and have their greatest strength there.
- 2003, Jon Bonk, Between Past and Future, →ISBN, page 21:
- The primary but not exclusive focus of AD2000 became the 10/40 Window, a term coined for the area of the world between ten degrees and forty degrees north latitude, stretching from northern Africa and southern Spain to Japan and the norther Philippines.