Gain a better understanding of medical terminology by searching our dictionary of more than 1,300 terms.


Filter By Alphabet
All terms
  • occiput

    The back of the head.

  • obstetrics

    The branch of medicine that deals with the care and treatment of women during pregnancy and childbirth.

  • obsessive-compulsive

    Marked by a need to repeatedly perform certain behaviors or rituals.

  • obsession

    An ongoing preoccupation with an idea.

  • obesity

    Having too much body fat. A weight more than 20% above the normal range.

  • nosocomial

    Having to do with the hospital. For example, an nosocomial infection is one that’s acquired during hospitalization.

  • norepinephrine

    A hormone produced by the adrenal medulla and certain sympathetic nerve fibers.

  • nonunion

    Failure of the ends of a broken bone to mend.

  • node

    A swelling, knot or knob.

  • nocturia

    Excessive urination at night.

  • nit

    The egg of a louse.

  • night blindness

    A reduced ability to see in dim light. May be caused by a vitamin-A deficiency or glaucoma.

  • nicotine

    A highly toxic and addictive component of tobacco. While the amounts obtained from smoking may not be enough to be…

  • nevus

    A mole or other colored spot on the skin.

  • neutrophil

    A mature white blood cell with a three- to five-lobed nucleus.

  • neurosis

    An emotional disorder that can interfere with a person’s ability to lead a normal life.

  • neuropathy

    Disease of the nervous system or of an individual nerve.

  • neuron

    A nerve cell.

  • neuroma

    A benign but sometimes painful tumor growing on a nerve.

  • neurology

    The branch of medicine that pertains to the nervous system.

  • neurofibromatosis

    An inherited disorder that causes dark spots on the skin and tumors of the skin, peripheral, optic and acoustic…