【Wharf】 , 【dock】 ,  【pier】 ,  【quay】 ,  【slip】 ,  【berth】 ,  【jetty】 ,  【levee】  signify a structure used by boats and ships for taking on or landing cargo or passengers.

【Wharf】 applies to a structure projecting from the shore that permits boats or ships to lie alongside for loading or unloading.

【Dock】  is usually interchangeable with  【wharf】 but can be restricted to signify an enclosed basin which permits the entrance of a vessel for loading or unloading or which, with floodgates and a method of exhausting water, can be used for building or repairing ships.

【Pier】  is interchangeable with  【dock】  or  【wharf】 especially as applied to a large or long structure shooting out quite a distance into a body of water.

【Quay】 usually refers to an artificial enbankment lying along or projecting from a shore and mainly used for loading or unloading; the term normally applies to wharves or piers characteristic of small places.

【Slip】 can apply to a sloping ramp usually constructed or used where the shore is high and shore water shallow, but it, like  【berth】 , can denote the space between two piers or wharves which gives room for a ship when anchored or not in use, and is more common for such a space intended or used for ferryboat landings or boardings.

【Jetty】 although commonly applied to a structure serving as a breakwater for a harbor applies also to a small and usually not very substantial 【pier】 of timbers.

【Levee】  primarily applies to an embankment for confining or restricting floodwaters but in the South and West, where a 【levee】 is often used for landing, the term is often the equivalent of  【quay】 .