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[syn: dilator, dilater]
The Collaborative International Dictionary of English v.0.48:
Dilator \Di*lat"or\, n. [See Dilate.]
   1. One who, or that which, widens or expands.
      [1913 Webster]
   2. (Anat.) A muscle that dilates any part.
      [1913 Webster]
   3. (Med.) An instrument for expanding a part; as, a urethral
      dilator.
      [1913 Webster]
WordNet (r) 3.0 (2006):
dilator
    n 1: a muscle or nerve that dilates or widens a body part
    2: a drug that causes dilation
    3: a surgical instrument that is used to dilate or distend an
       opening or an organ [syn: dilator, dilater]