Tendon: A fibrous cord by which all muscle attaches to bone.

Tensile Stress: Stress directed along the longitudinal axis. Pulling or stretching in a linear fashion.

Termination codon (or stop codon): is a nucleotide triplet within messenger RNA that signals a termination of translation. Proteins are unique sequences of amino acids, and most codons in messenger RNA correspond to the addition of an amino acid to a growing protein chain — stop codons signal the termination of this process, releasing the amino acid chain. In the standard genetic code, there are three stop codons: UAG ("amber"), UAA ("ochre"), and UGA ("opal" or "umber"); several variations to this most common set are known.

Therapy: The use of modalities, or machines, to augment the chiropractic adjustment. May include ultrasound, electrical muscle stimulation, traction, massage, heat/cold, infrared, laser, and others.

Thermography: A diagnostic procedure that images heat from body surfaces.

Thoracic vertebrae: There are twelve vertebrae in the thoracic or upper-back portion of the spine. They are labeled T1 through T12.

Tinnitus: A sensation of noise (such as ringing or roaring) in the ears that may be audible or inaudible. Audible tinnitus is usually associated with a muscular tic or vascular bruit. Inaudible tinnitus can be heard only by the person affected and may be associated with obstruction of the external auditory canal or a disturbance of the auditory nerve and/or the central nervous system.

TMJ Dysfunction: TMJ Dysfunction is a problem with the alignment of the tempromandibular joint of the jaw. When the junction of the jaw is degenerated, or damaged, several problems such as headaches, jaw pain, sinus problems, stiffness in the jaw, muscle tension in the face, head, neck and shoulders can occur. Damage can be to the disk material, the joint capsule, the muscles or the actual jaw bone.

Torticollis: Involuntary spasms of the musculature of the cervical spine (neck).

Tortipelvis: Involuntary spasms of the musculature of the lumbar spine (low back).

Topset: The distance from the top of the head to the top of a vehicles head restraint.

Traction: A specific directional force applied to the spine for a specific duration of time, used to reduce swelling, ease muscle spasms, or assist in the realignment of vertebral structure.

Truncate: To shorten, to cut short. From the Latin "truncare" meaning to cut short or mutilate from truncus, trunk. Ex: A malformation (birth defect) may truncate a limb. A mutation may create a stop codon that truncates a protein. Surgeons may truncate a sensory nerve to reduce pain transmission.