sigma factor n.
A protein component of RNA polymerase that determines the specific site on DNA where transcription begins.
noun, Physics. 1. an unstable hyperon having positive, negative, or zero electric charge and strangeness −1. Symbol: Σ.
adjective 1. having the form of the Greek sigma or the letter S. adjective 1. shaped like the Greek letter sigma or the Roman S
noun 1. defective pronunciation of sibilant sounds.
adjective 1. shaped like the letter C. 2. shaped like the letter S. 3. of, relating to, or situated near the sigmoid flexure of the large intestine. adjective 1. shaped like the letter S 2. of or relating to the sigmoid colon of the large intestine noun 3. See sigmoid colon sigmoid sig·moid (sĭg’moid’) or […]