Webster's New World Medical Dictionary

tissue
A group or layer of cells that perform spe-
cific functions. For example, muscle tissue is a
group of muscle cells.
titer
The concentration of a substance in a fluid,
such as the concentration of an antibody in blood.
The titer reflects the amount of the substance in the
fluid. Sometimes also spelled titre.
titre
See 
titer.
TMA
Trimethylaminuria. See 
fish-odor syndrome.
TMJ
Temporomandibular joint.
TMJ
syndrome
Temporomandibular joint
syndrome.
tobacco
A South American herb (Nicotiana
tabacum) whose leaves contain 2 to 8 percent nico-
tine and serve as the source of both smoking
and smokeless tobacco and the basis of great health
hazards.
toc-, toco-
Prefix meaning childbirth, as in tocol-
ysis (the slowing or halting of labor). Sometimes
spelled tok- and toko-.
tocolysis
The slowing or halting of labor during
the birth process.
tocolytic
Relating to the inhibition, delaying, or
halting of labor. For example, a tocolytic drug is a
medication that deters labor.
tocophobia
Fear of childbirth.
tocus
Labor, childbirth.
toddler’s fracture
See 
fracture, toddler’s.
toe sign
See 
Babinski reflex.
toenail
A tough, protective plate that is produced
by living skin cells in the toe. A toenail consists of
several parts, including the nail plate (the visible
part of the nail), the nail bed (the skin beneath the
nail plate), the cuticle (the tissue that overlaps the
plate and rims the base of the nail), the nail folds
(the skin that enfolds the frame and supports the
nail on three sides), the lunula (the whitish half-
moon at the base of the nail), and the matrix (the
hidden part of the nail unit under the cuticle).
Toenails grow from the matrix. They are composed
largely of keratin, a hardened protein that is also