| Noun | 1. | rhomboid muscle - any of several muscles of the upper back that help move the shoulder blade skeletal muscle, striated muscle - a muscle that is connected at either or both ends to a bone and so move parts of the skeleton; a muscle that is characterized by transverse stripes greater rhomboid muscle, musculus rhomboideus major, rhomboideus major muscle - rhomboid muscle that draws the scapula toward the spinal column lesser rhomboid muscle, musculus rhomboideus minor, rhomboid minor muscle - rhomboid muscle that draws the scapula toward the vertebral column and slightly upward |