To bring to an end; close: concluded the rally with the national anthem. See Synonyms at complete. To bring about (a final agreement or settlement): conclude a peace treaty. To reach a decision or form an opinion about. See Synonyms at decide. To arrive at (a logical conclusion or end) by the process of reasoning; infer on the basis of convincing evidence: The jury concluded that the defendant was innocent. Obsolete To confine; enclose. To come to an end; close. To come to a decision or agreement.