Radialis
/ˌreɪdiˈælɪs/
Relating to the radius bone or the radial side of the forearm.
Radius
/ˈreɪdiəs/
The shorter of the two bones of the forearm, on the thumb side.
Ramus
/ˈreɪməs/
A branch of a nerve, artery, or bone (e.g., the ramus of the mandible).
Raphe
/ˈreɪfi/
A groove, ridge, or seam in an organ or tissue marking the line of junction of two halves.
Receptor
/rɪˈsɛptər/
An organ or cell able to respond to light, heat, or other external stimulus and transmit a signal to a sensory nerve.
Rectum
/ˈrɛktəm/
The final section of the large intestine, terminating at the anus.
Rectus Abdominis
/ˈrɛktəs æbˈdɒmɪnɪs/
The 'six-pack' muscle; a long muscle extending the length of the front of the abdomen.
Rectus Femoris
/ˈrɛktəs ˈfɛmərɪs/
One of the four quadriceps muscles, situated in the middle of the front of the thigh.
Recurrent
/rɪˈkʌrənt/
Running back in the opposite direction (e.g., recurrent laryngeal nerve).
Renal
/ˈriːnəl/
Relating to the kidneys.
Respiration
/ˌrɛspɪˈreɪʃən/
The action of breathing; the exchange of gases between an organism and its environment.
Rete
/ˈriːti/
An elaborate network of blood vessels or nerve fibers.
Reticulocyte
/rɪˈtɪkjʊloʊsaɪt/
An immature red blood cell without a nucleus.
Retina
/ˈrɛtɪnə/
A layer at the back of the eyeball containing cells that are sensitive to light.
Retinaculum
/ˌrɛtɪˈnækjʊləm/
A band of thickened deep fascia which holds tendons in place (e.g., at the wrist or ankle).
Retraction
/rɪˈtrækʃən/
Moving a body part backward, such as pulling the scapulae toward the spine.
Retroperitoneal
/ˌrɛtroʊˌpærɪtəˈniːəl/
Situated or occurring behind the peritoneum (e.g., the kidneys).
Rhomboid
/ˈrɒmbɔɪd/
Diamond-shaped muscles (Major and Minor) that act to retract the scapula.
Rib
/rɪb/
One of the series of curved bones articulated with the spine and protecting the thorax.
Risorius
/rɪˈzɔːriəs/
A narrow facial muscle that pulls the corner of the mouth laterally (the smiling muscle).
Rotation
/roʊˈteɪʃən/
The action of rotating around an axis or center (e.g., turning the head).
Rotator Cuff
/ˈroʊteɪtər kʌf/
A capsule of four tendons and muscles that stabilize the shoulder joint.
Rugae
/ˈruːɡiː/
Ridges or folds in the lining of an organ, such as the stomach or vagina.