I’m referring to this:

a marina dock in Port of Seattle with several boats moored on either side

image: Harbor Island Marina in Port of Seattle (probable source: portseatlle.org)

I added a red arrow.

Example sentence:

Boats lined both sides of the [. . .], bobbing quietly under the blue sky.

  • 9
    That's a pier.
    – RegDwigнt
    Apr 10, 2015 at 11:45
  • 1
    Probably piers, or walkways. In Norfolk, home of the Norfolk Broads, and many hundreds of miles of river bank, there is a local word staithe. It is of believed Viking origin and exists at other places in Eastern England which were influenced by medieval Danish.
    – WS2
    Apr 10, 2015 at 11:47
  • 2
    In the photo, it is specifically a floating marina dock.
    – ermanen
    Apr 10, 2015 at 16:31
  • 2
    I've most commonly heard it called a "dock" (here in Minnesota, where there are many such structures).
    – Hot Licks
    Apr 10, 2015 at 17:44
  • 10
    If, like the one in the picture, it floats, then it's a 'pontoon'. The vertical pieces which are inserted into the bed of the river are 'pilings'. The machine which inserts them is called a 'pile driver'. If it doesn't float then it's a 'pier' (large) or a 'jetty' (small). If you don't know or care whether it floats or not then the generic term is a 'mooring'. Collectively a bunch of moorings form a 'marina', one or more of which can often be found in a 'harbour'. In a larger version for ships it's a 'dock' or 'quay'. (British English)
    – A E
    Apr 10, 2015 at 21:07

9 Answers 9


It’s a pier or a dock or a wharf.

From Wikipedia:

In American English, a dock is technically synonymous with pier or wharf—any human-made structure in the water intended for people to be on.

The structure shown is clearly a human-made structure in the water intended for people to be on. Therefore, it is a dock in American English. Whether it is also a pier or wharf may vary depending on what part of the world you live in. Here it would also be called a pier.

Yes, it’s floating. But it’s still a floating pier or floating dock.

  • 5
    It's not a pier, dock, wharf or quay (source: OED). Piers and quays are solid structures, not floating, and quay is mostly use for structures that are "on land" rather than jutting into the water; a dock is an area of water; wharves are "on land". Apr 10, 2015 at 14:07
  • 5
    @DavidRicherby - you sure that there is no definition of 'dock' that includes something like a "structure extending alongshore or out from the shore into a body of water, to which boats may be moored"?
    – Brendan
    Apr 10, 2015 at 14:18
  • 4
    @DavidRicherby In American English, a dock is technically synonymous with pier or wharf—any human-made structure in the water intended for people to be on. You will note that the picture is of a human-made structure in the water intended for people to be on. It is therefore a dock in American English.
    – tchrist
    Apr 10, 2015 at 14:33
  • 8
    I can confirm that the object in the picture can be called a "floating dock" in US English.
    – nobody
    Apr 10, 2015 at 16:12
  • 5
    Pier and dock jump to mind. The OED is just a dictionary. It doesn't determine usage. Wikipedia has it right and my experience with AmE is in accord (English of the American South and Southwest mixed with some of New England). The one thing it's not is a jetty, and imho it's too small for a wharf.
    – pazzo
    Apr 10, 2015 at 18:47

One word is jetty.

A landing stage or small pier at which boats can dock or be moored:
Ben jumped ashore and tied the rowboat up to the small wooden jetty


It appears that this is a British-English usage of the word and American English uses different words for various marine structures — or uses the same words in different ways. Despite that, Google images for jetty include the sort of thing illustrated in the question:

xlibber via Wikimedia Commons

...and some rather larger structures:

Luke Roberts via Wikimedia Commons

  • 5
    By the disparate answers thus far, it seems there 's little agreement; it seems there's room for a whole nother question here (if not already answered): what ARE the differences between a dock, wharf, quay, and jetty? Are they regional? I, for example, would never call the OP's picture a jetty, quay or pier; it is clearly a dock (which serves as a moorage). The "rather larger structure" is a pier. Piers are usually at the ocean, and have to be high above the water to accommodate tides. Apr 10, 2015 at 12:13
  • 1
    @Brian: docks only need to float on the water where there are tides. Apr 10, 2015 at 12:38
  • 7
    I always thought a jetty was simply a line of rocks sticking out in the water for waterbreaking purposes, not for getting off a boat. (but I see some definitions include the concept of pier).
    – Mitch
    Apr 10, 2015 at 13:58
  • 5
    There may be a US-UK difference. The top picture is definitely what I would call a jetty (in the UK).
    – Andrew Leach
    Apr 10, 2015 at 14:16
  • 6
    @AndrewLeach nice catch. yes, in AmE, a jetty is rocks or rubble. kids might play on it or maybe people fish, but a boat would not want to come close to it. A stone pier is an architected structure, designed and built for permanence, for larger ships to dock at. It would be solid (no pilings for water to rush around).
    – Mitch
    Apr 10, 2015 at 14:22

I'd usually refer to them as a "pontoon".

Jetty, dock, quay and pier all tend to be non floating. The OP's original picture is a device that floats with the tide but is kept in place by the upright poles so the boats are always at the same level as the "artifical ground level" created by pontoon.

The floats under the decking are often referred to as pontoons (much like the pontoon on a sea plane) but the decking and floats combined are what I would call a Pontoon

  • 4
    Pontoon might be used on the floating dock but I'm not sure if you can call the whole structure pontoon.
    – ermanen
    Apr 10, 2015 at 16:58
  • Best answer IMO, when you say pier I think of a pier like Brighton pier, when you say dock I think of docks like the London docks, but when you say pontoon I think of this.
    – ACarter
    Apr 10, 2015 at 18:02
  • 4
    technically, the pontoon is the floating boats under the decking.
    – Oldcat
    Apr 10, 2015 at 19:34
  • 2
    I believe @Oldcat is correct, in that the term "pontoon" strictly speaking refers to the floats, but it is fairly commonly used in the UK to refer to this sort of structure.
    – psmears
    Apr 10, 2015 at 21:04
  • Yes, pontoon or floating dock. Not quay, jetty, wharf or pier.
    – Lambie
    Jul 7, 2019 at 17:06

It is variously a pier, dock, wharf, jetty, or pontoon, depending on the local dialect and sophistication of the speaker. Call it a "dock", and everyone will understand what you're talking about while only a few of them will yell at you for mis-using terminology.

English has an enormous and highly-detailed vocabulary regarding ships and their support facilities that developed back when travel by water was the best way to get around. The distinctions have been fading in the past century or so, and many formerly-distinct terms are used interchangeably.


"A pier is a raised structure, including bridge and building supports and walkways, typically supported by widely spread piles or pillars. The lighter structure of a pier allows tides and currents to flow almost unhindered, whereas the more solid foundations of a quay or the closely spaced piles of a wharf can act as a breakwater, and are consequently more liable to silting. Piers can range in size and complexity from a simple lightweight wooden structure to major structures extended over 1600 metres. In American English, pier may be synonymous with dock." "A jetty is a structure that projects from the land out into water. Often jetty refers to a pier, wharf, dock, breakwater." from wikipedia. so its a jetty and a pier/dock. hope that helps


The first word that came to mind for me was "pier." Several others have noted that "dock" and "wharf" are also appropriate, which is entirely true.


The object in the original picture is, in British English, without doubt a 'pontoon'. If there is any doubt, confusion or conflicting suggestion of any merit, it will only be due to any variations between British and American English.

  • 1
    Not my downvote. Please provide support for your answer, otherwise you are only repeating somebody else's answer and expressing your personal viewpoint.
    – Mari-Lou A
    Apr 11, 2015 at 10:47
  • 1
    In the US a "pontoon" would most definitely be a floating object, but one that was only loosely moored, by ropes from an anchor, eg.
    – Hot Licks
    Apr 11, 2015 at 13:00
  • 1
    I suspect the distinction, in this case, comes down less to Br vs Am English, but rather to the level of sophistication of the speaker; to those not informed of proper nautical terminology, all of the words proposed are, for the most part, used interchangeably Apr 12, 2015 at 14:06

If pontoon referred to the whole structure there'd be no need for the expression pontoon bridge. As someone who read far too much military history as a child, I can assure you that it does exist.

  • English isn't as regimented as some would imagine it to be. From AHDEL: pontoon b. A floating structure that serves as a dock. >> Explains the downvote (not mine; new people here need some rep points so that they can give comments). Apr 11, 2015 at 23:23

Boardwalk - a path for pedestrians , typically made out of wood and running alongside the beach. Source: English Dictionary

  • You might want to consider putting a link to a dictionary site with this definition.
    – 3kstc
    Jul 14, 2017 at 1:27

Not the answer you're looking for? Browse other questions tagged or ask your own question.