H zone
relatively pale zone traversing the center of the A band of a sarcomere, visible in relaxed muscle fibers; consists of the central portion of thick (myosin) filaments that are not overlapped by thin (actin) filaments
en-US/ˈeɪt͡ʃ ˈzoʊn/
en-GB/eɪt͡ʃ ˈzəʊn/