| A | B |
|---|
| aft | toward the rear of the ship |
| armillary sphere | skeleton model of celestial sphere |
| amidships | the middle of the ship |
| astrolabe | measures latitude |
| back-staff | also known as Davis quadrant |
| ballast | any heavy material placed low in ship to increase stability |
| barometer | measures atmospheric pressure |
| bearing dial | determined position of sun and moon when Pole Star was not visible |
| bilge | lowest part of ship's hull |
| bireme | Greek or Phoenician fighting ship |
| bow | the front of a vessel |
| caravel | small three-masted vessel |
| carvel | planks laid close together on their edges |
| cartographer | mapmaker |
| chip log and reel | device for measuring speed of vessel |
| chronometer | device for keeping time independent of ship's motion |
| clinker (lapstrake) | edges of planks are overlapped |
| cog | 12th century northern European trading vessel |
| draft | depth of water required to float a ship |
| hull | outer body of a vessel |
| fore | front part of a ship |
| gunwale | top rail of the side of a ship |
| hand lead and line | means of finding depth of water near coasts |
| keel | backbone of the ship |
| mast | vertical pole that supports the sails |
| meridian | imaginary circle passing through the poles |
| mizzenmast | third mast |
| nao | 14th century square-rigger with two to four masts |
| pilot | person who navigates a vessel |
| poop deck | partial deck above the main deck located aft |
| port | left side of a ship |
| rudder | device near the stern to control direction |
