Final answer:
The correct term for both a landing pier for a ship and a deduction from one's pay as a penalty is 'dock'.
Step-by-step explanation:
The term that can mean a landing pier for a ship, or to deduct from one's pay as a penalty, is dock. A quay is similar to a dock in that it's a structure on the shore for loading and unloading ships, but it doesn't have the same implication for wage deductions. A port is a location on a coast or shore containing one or more harbors where ships can dock and transfer people or cargo to or from land. Mulct is a term for a fine or penalty, usually in a legal or formal context, unrelated to the docking of ships.