Port. Starboard. Head. Tack. Lee. Jibe. All these darn words that keep regular folks from understanding sailors! Why can't we just speak regular English?
It turns out that practically everything humans do has some special terminology of its own. Listen to your doctor or dentist sometime when they're poking around you. You'll rarely hear words like left, right, up or down. That's a good thing, because if you're lying down and the doc is standing at your feet, what's "Up?"- would it be towards the ceiling, or towards your head? Is "left" from the doc's left, or your left? Hence words like “anterior” and “posterior” get used to make everything clear. (We've all heard stories of operations done on the wrong side of someone's body, so these concerns aren't trivial.)
Same on a boat. If I stand at the bow, turn around and yell "Turn left," whose left is it? It's all about being unambiguous; having words that mean exactly the same thing to everyone, everywhere.
So we have the terms Port and Starboard. "Starboard" goes far back before boats were steered with rudders mounted in the center of the stern (back end); instead there was a steering oar on the right side (most skippers were right-handed so that makes sense). "Steering board" got shortened to "Starboard" over time. With the steering board on the right, you wouldn't want to bring your boat up to the dock against it; you'd damage it. Hence, "port" must be on the left. If I yell “Turn to port!” the skipper knows exactly what direction I mean.
Some of our terms make it into the English language. We've all used "taking another tack" when we decide to try a different way of doing something. "Tacking" on a sailboat is making a turn where the bow passes through the wind and the sails move from one side to the other - it’s a way to change direction.
Have you ever "given some leeway," maybe offering someone some extra time to do a project or giving them some more room to work? The "leeward" side of the boat is the side away from where the wind is coming from. If there's land on that side, the sailor tries to stay away from it or there's danger that the wind will blow the boat too close and run it aground. Having some extra space on the lee side is a good, safe thing to do!
“Giving leeway” also comes into play because a sailboat on your leeward side may have its wind cut off by the sails of your boat, making it hard for that skipper to control her boat. A windward boat has to allow for that and move out of the way - it must give leeway to the leeward boat to avoid a collision with it.
OK, one more: Why is a toilet called a "head?" For this one I refer to www.toiletmuseum.com, which tells us that back in the fifteenth century the front end of the ship was called the head, and the toilet was often placed there so the ocean spray would constantly clean the area. The bouncing around at the bow meant that even manly men had to SIT DOWN when using the head, a shipboard rule still in place today no matter where the throne is placed on the boat.
Avast, ye salty dawgs! Haul in the mizzen, hoist the main, and get ye to the sheets!
Look those up.