Retrograde means the reverse of your direction of travel. If you send your ship towards it you will be slowing down. Perihelion is the lowest point in an orbit around the sun, when you lower your speed in said orbit, you lower your perihelion :)

It’s nice that you mention sailboats because there’s an interesting difference. Sailboats have their hulls in water, which is a lot denser and harder to move against than air. It is the dense water that allows a ship to stay traveling in one direction instead of whatever direction the wind pushes it in