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Drugs and diseases reference index

Drugs and diseases reference index

Medical Dictionary Definitions A-Z List

Medical Dictionary Definitions A - Z - «N»:

  1. Nyctophobia Nyctophobia
    Nyctophobia: Pathological fear of the dark, an abnormal and persistent dread of the dark. Sufferers experience anxiety even though they may rationally realize that the dark does not pose a threat commensurate with their fear. Formed from the Greek "nyx" (night) and the Greek "phobos" (fear). "N...
  2. Nymph Nymph
    Nymph: A nymph is a stage in the life cycle of certain arthropods, as ticks and lice. (Not all nymphs are in Greek mythology.) There are three stages in the life cycle of lice: the nit, the nymph, and the adult. The nymph stage comes between a nit and an adult louse. Nits are lice eggs. They are ha...
  3. Nystagmus Nystagmus
    Nystagmus: Rapid rhythmic repetitious involuntary (unwilled) eye movements. Nystagmus can be horizontal, vertical or rotary....