Webster's New World Medical Dictionary

microhematuria
See 
blood in the urine.
microorchidism
Abnormally small testes. To
determine if the testes are too small, a device
called an orchidometer is used that permits a testis
to be compared to a series of plastic ovals (like
miniature American footballs) of differing sizes.
Microorchidism is a diagnostic feature, for example,
of Prader-Willi syndrome and certain other multiple
malformation syndromes. Microorchidism may also
result from shrinkage (atrophy) of the testis due to
damage, as from mumps. The opposite of
microorchidism is macroorchidism. See also
micropenis.
micropenis
An abnormally small penis. In med-
ical practice, the dimension of the penis that is
measured is the length. The measurement is taken
along the upper surface of the shaft of the penis to
the tip, using a measuring tape or, preferably, a
ruler. The ruler is pressed firmly into the soft tissue
over the pubic bone (the symphysis pubis) because
in obese boys and men, a seemingly small penis may
be partly engulfed by the fat pad at its base and actu-
ally be normal in length. Normal standards are
available for penis length. True micropenis may
reflect failure of normal hormonal stimulation or
failure of normal development (a birth defect). See
also 
microorchidism.
microphallus
See 
micropenis.
microphthalmia
An abnormally small eye.
Microphthalmia is a congenital malformation of the
globe, a birth defect of the eye. A related term,
anophthalmia, indicates that there is no eye at all.
Also known as microphthalmos.
microscope
An optical instrument that augments
the power of the eye to see small objects. Most opti-
cal microscopes today are compound microscopes.
microscope, compound
A microscope that
consists of two microscopes in series, the first serv-
ing as the ocular lens (close to the eye), and the
second serving as the objective lens (close to the
object to be viewed).