This volume covers more than 200 years of recording specific language in German explanatory dictionaries. For the first time, the comparative analysis of six dictionaries from the 18th to the 20th century provides reliable data which subject areas were covered lexicographically and which special methods of marking were used. Nautical language serves as an example to show constancy and changes in adding new specific vocabularies in the above mentioned time period. A broad overview of specific language research since the 19th century rounds off the book.