O que significa tiller ?

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@Joao054 if you use a search engine like google to look up "boat tiller" it will show you a lot of different examples, which is probably more helpful than a single image because there are different styles/appearances. But it basically is a long handle leading to the back of a small boat. They push that long stick handle to the right or left to help steer the boat in the water. So just imagine a long stick that is attached to the back of a boat, the handle bending in towards where you sit so you can reach it easily. The rudder is like a fin underneath the back of the boat, and the long stick handle up above it is the tiller that is used to tilt it right or left to steer things. That's the basic idea.

If the ship is big enough to have a steering wheel, then the tiller for that type of steering is either part of a system of ropes or part of a system with levers (often hidden from view) which help to convert the turning of the wheel into moving the rudder back and forth to change direction right or left. So there's still a part they call a tiller that helps the ship steering work, but it's not as obvious as the basic kind of tiller that you can see on smaller boats.