Dictionary of Marketing Terms: supplement line
supplement line
extra field in a computer file record used for additional address information beyond that required for most residential addresses, such as company name, title, or apartment-building name. Without a supplement line, the additional information would have to be omitted, at some risk of undeliverability, or fitted into the record by abbreviating elements of the name and address. It has been found that many people object to receiving mail addressed with a shortened version of their name.
