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• a short ad in a newspaper or magazine (usually in small print) and appearing along with other ads of the same type

  synonym	classified adclassified advertisement
  hypernym	newspaper adnewspaper advertisement
  hyponym	want ad

• arranged into classes

  antonym	unclassified
  similar	categorisedcategorizedgroupedsorted

• official classification of information or documents; withheld from general circulation

  antonym	unclassified
  similar	confidentialeyes-onlyrestrictedsecretsensitivetop-secret