Wilmer Lanier Barrow (July 26, 1903 – August 29, 1975) was an American electrical engineer, inventor, teacher, industrial manager, and a counselor to government agencies. He obtained a BSEE degree in 1926 from Louisiana State University, and a doctorate from the Technical University of Munich in 1931. During the pre-World War 2 development of radar at Massachusetts Institute of Technology, Barrow performed research on microwaves, inventing waveguide in 1936 and the horn antenna in 1938. He was vice president for research, development and engineering of the Sperry Rand Corporation.