Lexical Analysis of Nautical and Marine Engineering Corpora: Similar or Different Lexicographic Results

English for Maritime Purposes comprises a variety of different registers. However, most of the dictionaries and glossaries are dedicated either to General Maritime English or Nautical English, while other aspects of the maritime industry are poorly covered by specialized lexicographic material, especially as regards formal dictionaries. Considering that the main classification onboard ship in terms of the crew and operational systems is related to the Deck and the Engineering Department, we sought to explore the similarities and differences between the technical lexes of the two areas, in order to see whether separated dictionaries and glossaries might be required, or a common maritime one would suffice. To test and measure the tackled technical vocabularies, we utilized contemporary corpus linguistics methods and software. The results show significant differences in the key vocabulary of the compared corpora. The findings clearly and once more call for special attention and focus when it comes to the interpretation of maritime lexis, as well as for establishing a clear distinction between English for Nautical and for Marine Engineering purposes. Keywords: maritime English, nautical English, marine engineering, corpus, vocabulary, lexis, frequency, keywords, word list, technical dictionary