random sample

from WordNet (r) 3.0 (2006)

random sample
    n 1: a sample in which every element in the population has an
         equal chance of being selected
    2: a sample grabbed at random

from Moby Thesaurus II by Grady Ward, 1.0

78 Moby Thesaurus words for "random sample":
      accidentality, actuarial calculation, adjunct, adventitiousness,
      barometer, break, casualness, chance, component, contingent,
      cross section, destiny, detachment, detail, division, dole, fate,
      feeler, flukiness, fortuitousness, fortuity, fortune, fraction,
      gamble, good fortune, good luck, hap, happenstance, happy chance,
      heedless hap, how they fall, indeterminacy, indeterminateness,
      installment, item, law of averages, lot, luck, moira, opportunity,
      parcel, part, particular, percentage, pilot balloon, portion,
      principle of indeterminacy, probability, probe, problematicness,
      quadrant, quarter, quota, remainder, risk, run of luck, sample,
      sampling, section, sector, segment, serendipity, share, sound,
      sounder, statistical probability, straw vote, subdivision,
      subgroup, subspecies, the breaks, theory of probability,
      trial balloon, uncertainty, uncertainty principle, weather vane,
      weathercock, whatever comes