trier

from WordNet (r) 3.0 (2006)

trier
    n 1: one (as a judge) who examines and settles a case
    2: one who tries [syn: {trier}, {attempter}, {essayer}]

from The Collaborative International Dictionary of English v.0.48

Trier \Tri"er\, n. [From {Try}.]
   1. One who tries; one who makes experiments; one who examines
      anything by a test or standard. --Boyle.
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   2. One who tries judicially.
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   3. (Law) A person appointed according to law to try
      challenges of jurors; a trior. --Burrill.
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   4. That which tries or approves; a test. --Shak.
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