(1) A defect is a departure of a quality characteristic from its intended level or state that occures with a severity sufficient to cause an associate product or service not to satisfy intended normal, or foreseeable, usage requirements.
(2) According to ISO 9000:2000
non-fulfillment of a requirement (3.1.2) related to an intended or specified use
Note 1 - The distinction between the concepts defect and nonconformity (3.6.2) is important as it has legal connotations, particularly those associated with product liability. Consequently the term “defect” should be used with extreme caution.