Frederick Mortimer "Cap" Irish (May 16, 1870 – April 12, 1941) was an American football coach, college athletics administrator, and science instructor. He served as the first head football coach at the Territorial Normal School, renamed Tempe Normal School in 1903 and now known as Arizona State University, coaching from 1896 to 1906 and compiling a record of 12–8. Territorial Normal did not field a football team in 1897, 1898, or 1901. Irish was also the first athletic director at Territorial/Tempe Normal, serving from 1896 to 1913. In addition, he taught science at the school.
Irish graduated from the University of Iowa in 1895 with a Bachelor of Science degree. He taught in his hometown of Dubuque, Iowa, before moving to Arizona. Irish died in 1941. Irish Hall, a residence hall at Arizona State University, is named for him.