International Standard Serial Number International Standard Serial Number An International Standard Serial Number (ISSN) is an eight-digit serial number used to uniquely identify a serial publication. The ISSN is especially helpful in distinguishing between serials with the same title. ISSN are used in ordering, cataloging, interlibrary loans, and other practices in connection with serial literature. The ISSN system was first drafted as an International Organization for Standardization (ISO) international standard in 1971 and published as ISO 3297 in 1975. ISO subcommittee TC 46/SC 9 is responsible for maintaining the standard. When a serial with the same content is published in more than one media
Opposite (semantics) has no word that stands in opposition to it (hence the unanswerability of "What is the opposite of platypus?"). Other words are opposable but have an accidental gap in a given language's lexicon. For example, the word "devout" lacks a lexical opposite, but it is fairly easy to conceptualize a parameter of devoutness where "devout" lies at the positive pole with a missing member at the negative pole. Opposites of such words can nevertheless sometimes be formed with the prefixes "un-" or "non-", with varying degrees of naturalness. For example, the word "undevout" appears in Webster's dictionary of 1828, while