g.

MASTURBATION. Excitement of the sexual organs by the hand.

MEATUS. Canal or passage. External opening of a canal.

MEDIAN SECTION. An operation for stone in the bladder in which the
perineum and part of the urethra are cut; the prostatic portion of the
urethra is dilated to introduce forceps and withdraw the stone.

MEDULLA OBLONGATA. Described on page 90; illus. page 96.

MELANCHOLIA. A mild form of insanity attended with great gloom and
mental depression.

MEMBRANOUS. Of the nature or construction of membrane.

MENINGES. Membranes covering the brain.

MENORRHAGIA. Immoderate monthly flow.

MENSES. Monthly flow of the female. See page 686.

MENSTRUATION. The bloody evacuation from the womb.

MENSTRUUM. A solvent; as water, alcohol, etc.

MESENTERIC GLANDS. Glands about the peritoneum which secrete lymph.

MESENTERY. Described on page 49.

MIASM, MIASMA. A poisonous, gaseous exhalation from decaying vegetation,
or from the earth.

MIDWIVES. Females who attend women at childbirth.

MISCARRIAGE. Defined on page 682.

MOLECULE. A minute portion of any body.

MONADS. The smallest of all visible animalcules.

MONOMANIA. Insanity on one subject.

MUCO-PURULENT. Composed of mucus and pus.

MUCOUS MEMBRANE. The thin, web-like lining to the canals and cavities
which secretes a fluid by which it is constantly lubricated.

MUCUS. A mucilaginous fluid found on the surface of certain membranes
which keeps them soft and pliable. See MUCOUS MEMBRANE.

MUSCLE. The structures of the body which execute movements.

MUSCULAR TISSUE. The flesh forming the muscles of the body.

MYALGIA. Muscular rheumatism.

N

NARCOTICS. Medicines which stupefy.

NECROSIS. Mortification or death of bone.

NERVINES. Defined on page 345.

NERVOUS TISSUE. That part of the body composed of nerve-fibres.

NEURALGIA. Described on page 635.

NICOTIN. A poisonous principle of tobacco.

NITROGEN. One of the gases in the atmosphere.

NODES. Hard lumps, principally found upon the bones in syphilis.

NOXIOUS. Injurious.

NYMPHOMANIA. Extreme desire for sexual intercourse in the female.

O

OBSTETRICAL. Relating or appertaining to childbirth.

OCCLUSION. Approximation or closure.

OEDEMA. See EDEMA.

OLFACTORY NERVE. The nerve employed in the sense of smell. Illus. page
111.

ONANISM. See MASTURBATION

OPACITY. Opaque condition of parts of the eye, causing blindness.

OPALESCENT. Reflecting a milky l