| Main Entry: | |
| Part of Speech: | adjective |
| Definition: | unfathomable |
| Synonyms: | abysmal, cavernous, deep, immeasurable |
| Main Entry: | marine/maritime |
| Part of Speech: | adjective |
| Definition: | concerning the sea |
| Synonyms: | Neptunian, abyssal, aquatic, coastal, deep-sea, hydrographic, littoral, maritime, natatorial, nautical, naval, navigational, oceangoing, oceanic, oceanographic, of the sea, pelagic, saltwater, sea, seafaring, seagoing, seashore, seaside, shore |
| Main Entry: | nautical/naval |
| Part of Speech: | adjective |
| Definition: | concerning ships, sea |
| Synonyms: | abyssal, aquatic, boating, cruising, deep-sea, marine, maritime, navigating, navigational, oceangoing, oceanic, oceanographic, pelagic, rowing, sailing, sailorly, salty, sea-loving, seafaring, seagoing, thalassic, yachting |
| Main Entry: | marine |
| Part of Speech: | adjective |
| Definition: | sea |
| Synonyms: | Neptunian, abyssal, aquatic, coastal, deep-sea, hydrographic, littoral, maritime, natatorial, nautical, naval, navigational, ocean-going, oceanic, oceanographic, pelagic, saltwater, sea, seafaring, seagoing, seashore, seaside, shore |
| Antonyms: | freshwater |
| Main Entry: | nautical |
| Part of Speech: | adjective |
| Definition: | sea |
| Synonyms: | abyssal, aquatic, boating, cruising, deep-sea, marine, maritime, naval, navigating, navigational, oceangoing, oceanic, oceanographic, pelagic, rowing, sailing, sailorly, salty, sea-loving, seafaring, seagoing, ship, thalassic, yachting |
| Main Entry: | plutonic |
| Part of Speech: | adjective |
| Definition: | solidified |
| Synonyms: | abyssal, cimmerian, igneous, infernal |
| Main Entry: | thalassic |
| Part of Speech: | adjective |
| Definition: | marine |
| Synonyms: | Neptunian, abyssal, aquatic, coastal, deep-sea, hydrographic, littoral, maritime, natatorial, nautical, naval, navigational, oceangoing, oceanic, oceanographic, of the sea, pelagic, saltwater, sea, seafaring, seagoing, seashore, seaside, shore |