Phi Sigma (ΦΣ) is an honor society for students of biological sciences. Phi Sigma was founded on March 17, 1915 at Ohio State University. It became a member of the Association of College Honor Societies in 1950. The Greek letters, Phi and Sigma, signify "fellows in science". The coat of arms contains the motto of the organization in Greek, which when translated means, "Truth shall spring from the earth." The coat displays the society's colors: white, yellow, and green.
Phi Sigma is reserved for students who have demonstrated interest in research, and are at the top of their class in their respective universities. At least one-fourth of their college training should include biological sciences.