The Collaborative International Dictionary of English v.0.48:

Constriction \Con*stric"tion\, n. [L. constrictio: cf. F.
   constriction.]
   1. The act of constricting by means of some inherent power or
      by movement or change in the thing itself, as
      distinguished from compression.
      [1913 Webster]

   2. The state of being constricted; the point where a thing is
      constricted; a narrowing or binding.
      [1913 Webster]

            A constriction of the parts inservient to speech.
                                                  --Grew.
      [1913 Webster]

WordNet (r) 3.0 (2006):

constriction
    n 1: a narrowing that reduces the flow through a channel [syn:
         constriction, bottleneck, chokepoint]
    2: tight or narrow compression [syn: constriction,
       coarctation]
    3: a tight feeling in some part of the body; "he felt a
       constriction in her chest"; "she felt an alarming tightness
       in her chest"; "emotion caused a constriction of his throat"
       [syn: constriction, tightness]
    4: the action or process of compressing