When you run a series of tests on something, it's called a trial. If you invent a computer game and want to run it through a trial before releasing it, you might hire a bunch of teenagers to play it.

A trial is also a court hearing to legally determine the result of a particular case. If your cousin is arrested for stealing her neighbor's dog, she may be put on trial. This term can also be used more generically, especially to talk about something being tried in the court of public opinion. The fate of music education is on trial in many school districts facing budget cuts.

Definitions of trial
  1. noun
    the act of testing something
    “in the experimental trials the amount of carbon was measured separately”
    “he called each flip of the coin a new trial
    synonyms: run, test
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    a quantitative or qualitative test of a substance (especially an ore or a drug) to determine its components; frequently used to test for the presence or concentration of infectious agents or antibodies etc.
    clinical test, clinical trial
    a rigorously controlled test of a new drug or a new invasive medical device on human subjects; in the United States it is conducted under the direction of the FDA before being made available for general clinical use
    double blind
    a test procedure in which the identity of those receiving the intervention is concealed from both the administrators and the subjects until after the test is completed; designed to reduce or eliminate bias in the results
    preclinical phase, preclinical test, preclinical trial
    a laboratory test of a new drug or a new invasive medical device on animal subjects; conducted to gather evidence justifying a clinical trial
    audition, tryout
    a test of the suitability of a performer
    field trial
    a test of young hunting dogs to determine their skill in pointing and retrieving
    fitting, try-on, trying on
    putting clothes on to see whether they fit
    MOT, MOT test, Ministry of Transportation test
    a compulsory annual test of older motor vehicles for safety and exhaust fumes
    pilot program, pilot project
    activity planned as a test or trial
    Snellen test
    a test of visual acuity using a Snellen chart
    ELISA, enzyme-linked-immunosorbent serologic assay
    an assay that relies on an enzymatic conversion reaction and is used to detect the presence of specific substances (such as enzymes or viruses or antibodies or bacteria)
    an assay that shows specific antigens in tissues by the use of markers that are either fluorescent dyes or enzymes (such as horseradish peroxidase)
    phase I, phase I clinical trial
    a clinical trial on a few persons to determine the safety of a new drug or invasive medical device; for drugs, dosage or toxicity limits should be obtained
    phase II, phase II clinical trial
    a clinical trial on more persons than in phase I; intended to evaluate the efficacy of a treatment for the condition it is intended to treat; possible side effects are monitored
    phase III, phase III clinical trial
    a large clinical trial of a treatment or drug that in phase I and phase II has been shown to be efficacious with tolerable side effects; after successful conclusion of these clinical trials it will receive formal approval from the FDA
    phase IV, phase IV clinical trial
    sometimes the FDA approves a drug for general use but requires the manufacturer to continue to monitor its effects; during this phase the drug may be tried on slightly different patient populations than those studied in earlier trials
    screen test
    a filmed audition of an actor or actress
    diagnostic assay, diagnostic test
    an assay conducted for diagnostic purposes
    bio-assay, bioassay
    appraisal of the biological activity of a substance by testing its effect on an organism and comparing the result with some agreed standard
    type of:
    attempt, effort, endeavor, endeavour, try
    earnest and conscientious activity intended to do or accomplish something
  2. noun
    trying something to find out about it
    “a sample for ten days free trial
    “a trial of progesterone failed to relieve the pain”
    synonyms: test, trial run, tryout
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    field test, field trial
    a test of the performance of some new product under the conditions in which it will be used
    alpha test
    (computer science) a first test of an experimental product (such as computer software) carried out by the developer
    beta test
    (computer science) a second test of an experimental product (such as computer software) carried out by an outside organization
    road test
    a test to insure that a vehicle is roadworthy
    trial balloon
    a test of public opinion
    test drive
    test of the roadworthiness of a vehicle one is considering buying
    type of:
    experiment, experimentation
    the testing of an idea
  3. noun
    the act of undergoing testing
    “candidates must compete in a trial of skill”
    synonyms: test
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    type of:
    attempt, effort, endeavor, endeavour, try
    earnest and conscientious activity intended to do or accomplish something
  4. noun
    (law) the determination of a person's innocence or guilt by due process of law
    “he had a fair trial and the jury found him guilty”
    “most of these complaints are settled before they go to trial
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    a trial that is conducted by a military court
    ordeal, trial by ordeal
    a primitive method of determining a person's guilt or innocence by subjecting the accused person to dangerous or painful tests believed to be under divine control; escape was usually taken as a sign of innocence
    Scopes trial
    a highly publicized trial in 1925 when John Thomas Scopes violated a Tennessee state law by teaching evolution in high school; Scopes was prosecuted by William Jennings Bryan and defended by Clarence Darrow; Scopes was convicted but the verdict was later reversed
    show trial
    a trial held for show; the guilt of the accused person has been decided in advance
    a trial that is invalid or inconclusive
    a new trial in which issues already litigated and to which the court has already rendered a verdict or decision are reexamined by the same court; occurs when the initial trial is found to have been improper or unfair due to procedural errors
    type of:
    legal proceeding, proceeding, proceedings
    (law) the institution of a sequence of steps by which legal judgments are invoked
  5. noun
    (sports) a preliminary competition to determine qualifications
    “the trials for the semifinals began yesterday”
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    type of:
    competition, contest
    an occasion on which a winner is selected from among two or more contestants
  6. noun
    an annoying or frustrating or catastrophic event
    “his mother-in-law's visits were a great trial for him”
    synonyms: tribulation, visitation
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    a severe trial
    type of:
    a cause of great suffering and distress
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