Category: U

  • Undulation

    A continuous wavelike motion or pulsation. An undulating motion.  

  • Undulant

    Rising and falling like waves, or moving like them.  

  • Undifferentiation

    An alteration in cell character to a more embryonic type or toward a malignant state.  

  • Undifferentiated connective tissue disease

    A connective tissue disease that does not fully meet the criteria for any of the well-defined rheumatological conditions such as rheumatoid arthritis, Sjogren’s syndrome, or systemic lupus erythematosus. Signs and symptoms of connective tissue disease must be present for several years. These may include polyarticular arthritis, Raynaud’s phenomenon, pleuritis, or pericarditis, among others. The patient…

  • Undertoe

    The displacement of the great toe underneath the others.  

  • Undercorrection

    In refractive eye surgeries such as LASIK, too small a change in shape of the cornea that results in inadequate focusing of light rays (failure of light to fall onto the retina).  

  • Underactive

    Functioning at less than full efficiency or productivity; said, for example, of glands such as the thyroid or the adrenals.  

  • Undecylenic acid

    An antifungal drug used topically to treat tinea pedis.  

  • Uncontrolled area

    For radiation protection purposes, an area occupied by the general public.  

  • Unconcern

    Profound uninterest or nonchalance out of proportion to societal norms. It is a characteristic of some brain diseases, including certain forms of brain injury, dementias, intoxications, and strokes.