The list isn’t divided on historical and modern dictionaries, considering that many links contains mixed content, and anyway, many historical terms are still used. However, you can also find specifically historical dictionaries on the list, so mind the descriptions, please.
Web-directories of nautical dictionaries
Online Nautical Dictionaries / termistri.refer.org Contains also non-English and multilanguage dictionaries. Among others, there are glossaries of maritime law terms, acronyms & abbreviations, oceanography, etymology and many, many more.
Bruzelius.info Maritime etymology and dictionaries.
Glossarist Naval dictionaries.
Dictionaries online, English only
Wikipedia glossary of Nautical terms.
William Falconer’s Dictionary of the Marine.
Browsable and searchable glossary based on printed edition, London 1780. English and French terms. (You can also find the printed version below, in the “Printed dictionaries, digitized” part.)
Nautical Sailing Terms & Nomenclature Contains detailed and described
plans of ships of the war, first and third rate. The scan comes from
Cyclopaedia, London 1728.
Lachlan and Elizabeth Macquarie Archive: Glossary: Nautical Terms, late 18th and early 19th .
The link found thanks to
Black Pearl Tales Archive.
A Glossary of Things Nautical and Piratical compiled by Captain Erinrua of Black Pearl Sails, at the Black Pearl Tales Archive.
Explanation of the Terms Used in Seamanship, 1794.
Archived at Black Pearls Sails by Captain Erinrua, from a now-defunct internet source.
Nautical Language at See the Sea.org
The link found thanks to
Black Pearl Tales Archive.
Seatalk.info Big Dictionary and Definitions of Sailing Terms at Sailinglinks.com
Sailors Choice Nautical Terms Index 1775 Naval Terms and Slang The link found thanks to
Molly Joyful’s List Of Useful Resources.
Origin of Navy Terminology The link found thanks to
Molly Joyful’s List Of Useful Resources.
Nautical phrases in The Phrase Finder / phrases.org.uk
Very comprehensive and detailed entries, with references and citations from printed literature. The link found thanks to
Molly Joyful’s List Of Useful Resources.
Nautical Glossary of Canadian Navy Maritime History Citations for Oxford English Dictionary by Alan H. Hartley.
Rob Ossian's Pirate Cove:
Modern Sailing Terminology Dictionaries online, English-other language or other language-English
English-many languages
Historical Dictionary of Mediterranean Nautical Terms by Alan H. Hartley.
An English-Spanish-Dutch-French dictionary of wind force terms used by mariners from 1750 to 1850 (pdf). Contains also multilingual sail names.
Danish
Maritim ordbog / jmarcussen.dk French
William Falconer’s Dictionary of the Marine.
Browsable and searchable glossary based on printed edition, London 1780. English and French terms. (You can also find the printed version below, in the “Printed dictionaries, digitized” part.)
Sailing Dictionary [English-French, French-English] Le langage des marins Base de Terminologie [English, French, German, Spanish] (choose “Ocean” of the expanded menu)
German
AboutSailing: Ein Wörterbuch der Segelbegriffe in verschiedenen Sprachen [German-English, English-German, German-French, French-German, German-Dutch, Dutch-German, German-Spanish, Spanish-German]
WEBTERM-Segelbote (both alphabetical and systematic)
Online-Segel-Wörterbuch Segel-Wörterbuch - sailing dictionary Greek
Ελληνικό-Αγγλικό λεξικό ιστιοπλοϊκών όρων / Ellēnikó-Anglikó lexikó istioploïkṓn órōn Italian
Dizionario MauroFornasari Paolo Ciraci: Dizionario dei termini nautici (only searchable)
Japanese
Japan Marine Affairs & Comprehensive Ocean Dictionary by Kiyofumi Nakauchi
Terms by alphabetical order and by subject. English-Japanese/Japanese-English, Spanish-Japanese/Japanese-Spanish, French-Japanese/Japanese-French, Portuguese-Japanese.
Polish
Żaglowce - terminologia (sailship details terminology, click green links)
Angielski dla żeglarzy (with commands, pdf)
Russian
Glossary of Nautical Terms: [American] English-Russian (pdf)
Spanish
Diccionario Náutico Abreviado Inglés-Español Rob Ossian’s Pirate Cove:
XVth Century Sailing Terminology Dictionaries online, not-English
Danish
Skibsterminologi (Wiki)
Den Store Maritime Ordbog lodsen.dk Jensines ordliste hillerodsejl.dk French
Glossaire maritime (Wiki)
Glossaire des termes de marine Glossaire de la marine Lexique maritime Dictionnaire maritime en ligne German
Liste seemännischer Fachwörter
A-M,
N-Z (Wiki)
Kleines Lexikon der Seemännischen Ausdrücke Marinelexikon Jan Maat’s kleines Seemannslexikon Greek
Το λεξικό των όρων της θάλασσας / To lexikó tōn órōn tēs thálassas Italian
Glossario dei termini marinareschi (Wiki)
Terminologia marinaresca Glossario Nautico Norwegian
Maritime uttrykk (Wiki)
Maritimstart - ordliste Polish
Bezan - Słownik Żeglarski SEL - Słowniczek żeglarski Portuguese
Terminologia náutica (Wiki)
Russian
Морские термины (Wiki)
Sailhistory.ru nesia.ru Spanish
Diccionario Náutico Diccionario Términos Marítimos Printed dictionaries, digitized
Alphabetical order by author. Collective works at top of the list, alphabetically by title.
A naval encyclopaedia: comprising a dictionary of nautical words and phrases: biographical notices, and records of naval officers …, Philadelphia 1880.
Nautical phraseology in English, French, Spanish and German, for use at the U.S. Naval Academy, Annapolis 1911.
Nuovo dizionario tascabile di marina italiano-inglese ed inglese-italiano…, Messina 1811.
Słownik morski, Warsaw 1929-36. (site navigation in Polish)
Diccionario de marinha que aos officiaes de Armada Nacional Portugueza by João Pedro d’Amorim, Lisbon 1841.
A dictionary of sea terms by A. Ansted, London 1898.
A complete nautical pocket dictionary. English-German and German-English by John Barten, Berlin 1911.
Allgemeines nautisches Wörterbuch mit Sacherklärungen: [German, English, French, Spanish, Portuguese, Italian, Swedish, Danish, Dutch] by Eduard Bobrik, Leipzig 1858.
Encyclopédie militaire et maritime. by marquis Louis Pierre François Adolphe Chesnel de la Charbouclais, Paris 1865.
An universal dictionary of the marine by William Falconer, London 1784.
Dictionnaire universel, historique et raisonné, français-hollandais de marine et de l'art militaire… by E. Gocvic et H. G. Jansen, The Hague, Amsterdam 1844.
A systematic dictionary of sea terms by Charles Grand-Pierre, New York 1928.
Glossaire nautique : répertoire polyglotte de termes de marine anciens et modernes by Auguste Jal, Paris 1848. (site navigation in French)
Dictionnaire polyglotte de termes militaires et de marine [French, Dutch, English, German] by H. M. F. Landolt, Leiden 1865-71.
Dictionnaire moderne des termes de marine et de la navigation à vapeur by François Frédéric Leméthéyer, Le Havre 1843.
Vocabulaire des termes de marine: anglois-françois et françois-anglois by baron Daniel Lescallier, Paris 1799 or 1800.
Dictionnaire des termes de marine français-espagnols et espagnols-français by C. L. Lhuillier et C. J. Petit, Paris 1810.
Diccionario marítimo español … contiene las equivalencias en francés, inglés e italiano… by José de Lorenzo [et al.], Madrid 1864.
New Spanish and English nautical, maritime and technical dictionary by Alfred Lutschaunig, London, Liverpool 1869.
Dictionnaire universel de marine… [French-English] by Charles Marchal, Paris 1862.
The British Mariner’s Vocabulary by J. J. Moore, London 1801.
The Midshipman’s or British Mariner’s Vocabulary (second edition) by J. J. Moore, London 1805.
Custom officers’ English-Chinese vademecum [phrasebook] by D. Okamoto, Shanghai 1915.
Illustrated nautical dictionary, unabridged by Howard Patterson, New York 1891.
Dictionnaire de la marine francoise, avec figures by Charles Romme, Paris 1813.
Veiledning i sømandskabet [Danish] by Jens Christian Schneider, Copenhagen 1817.
A nautical and technical dictionary of the English and Italian languages by Raffaele Settembrini, Naples 1879.
The Sailor’s Word-Book by William Henry Smyth, London 1867.
Zeemans woordenboek… Dictionnaire de marine… Naval dictionary… by A. C. Twent, Amsterdam 1813.