What is the difference between an ocean and a sea?

Size is important, Oceans ARE bigger than seas, ( smallest ocean Arctic 5,427,000 sq miles, largest sea Mediterranean 1,144,800 sq mi). But a sea is more or less enclosed and separated from the larger ocean by land.

The Mediterranean is completely surrounded by land with only the Straits of Gibraltar as an outlet, while the Bering Sea is separated from the Pacific to the south by only a narrow string of widely spaced islands. Seas generally are larger than gulfs, ( also "more or less enclosed and separated from the larger body of water by land.") but the Gulf of Mexico,615,000 sq mi ,is larger than the East China Sea, 482,300. Gulfs and seas are larger than bays (again "more or less enclosed and separated from the larger body of water by land.") "but The Bay of Bengal, 1,300,000 square miles is larger than the Mediterranean . A large inland saline lake without an outlet or connection to a larger body is also called a sea, such as the Caspian Sea, 152,239 square miles.. The Caspian, though saline and no outlet, is sometimes considered to be the world's largest LAKE, Lake Superior,largest fresh water body and with an outlet, 31,820 sq mi , is larger than the saline Dead Sea, 394 square miles. The Sea of Galilee is a small freshwater lake with a natural outlet, but it's called Sea anyway. Sometimes it's just a matter of what people call it, sea?

THE DIFFERENCE BETWEEN SEAS AND OCEAN ARE:
THE OCEAN IS LARGER THAN THE SEAS, AND
SEAS IS PARTIALLY ENCLOSED BY LAND.

According to:
http://school.discovery.com/schooladventures/planetocean/ocean.html

"You've heard of "one world?" Well, technically, all the world's oceans and seas are part of one continuous mass of seawater. But because the ocean is so big, humans have divided it up and named the different parts. There are five oceans and several dozen seas.* Seas are usually smaller than oceans and are partially enclosed by land. But otherwise, they're exactly the same thing."

Hope I've been some help. Welcome to AB!

Technically, all the world's oceans and seas are part of one continuous mass of seawater. Oceans are the largest uninterrupted expanses of water. Seas are usually smaller than oceans and are partially enclosed by land.

Side Note - The Caspian Sea is, strictly speaking, not really a sea but instead the world's largest lake.

The difference is a matter of size. The oceans are much larger than the seas. In many cases, the seas are considered to be subdivisions within an ocean. For example, the North Sea and the Caribbean Sea are considered to be part of the Atlantic.

An ocean is a large expanse of salt water, especially any of the Earth's five main such areas like the Atlantic, Pacific, Indian, Arctic, and Antarctic oceans.

A sea is a body of salt water that is surrounded by land.

http://www.answerbag.com/q_view/21033

An ocean is larger than a sea, and its only because a sea is partially enclosed by land....

In reality, there is no difference. They are two words that mean exactly the same thing. The word "ocean" comes from the Latin "oceanus" and "sea" comes from the Germanic word "see". English is a Germanic language in origin, but has absorbed over half its vocabulary from latin, either directly or via French, due to its history (the Norman invasion 1066 and the influence of the Roman catholic church). So, often there are two words for the same thing. In the Middle Ages, the Latin based words were more used by the upper classes and the Germanic ones by the lower, but, as the classes mixed and the Norman Invasion became part of history, the two words would be used interchangably.

I think the difference between "sea" and "ocean" is in the first place one of size and importance. An ocean is always large, a sea can be large or small, but never so large as the ocean itself. An ocean tends to be open, a sea is usually (but not always) closed and can be in the hinterland, too. An ocean is always deep, the sea can be deep or shallow.

Also, etymologically speaking, "ocean" comes from Greek, whereas "sea" is a pure Germanic word. Therefore, "ocean" is a more learned term: oceanography, oceanology. An ocean is often something unknown and mysterious, whereas the sea seems to be something more knowable and palpable.

In many cases and contexts, the two words are interchangeable.

But technically, it seems, the ocean always includes the sea.

if this was asked in "deep thoughts" i wonder if the answers would have been any different?

Oceans sound deeper than seas... other than that i have no idea... sounds too much the same when you think about it as geography :)

Mediterranean is not the largest sea Mediterranean (2.5 million km²). The largest sea is South China Sea (3.5 million km²).

Seas are much gayer then oceans. Oceans aref famous 2

Oceans are larger than seas in terms of size but actually they are the same because seas are large expanses of saline water connected with an ocean.

An ocean is larger in area than a sea

From http://www.newton.dep.anl.gov/askasci/env99/env131.htm

It's not a rigid definition. Seas are delineated by land masses, whether or not they are largely enclosed. They should also communicate with the ocean.
The Meditteranean and Black seas qualify here, because saltwater actually flows IN to both those bodies of water. The Caspian Sea is, strictly speaking, not really a sea but instead the world's largest lake. Why aren't the Gulf of Mexico, the Gulf of California, Hudson Bay, and the Bay of Bengal not called seas? No real reason. It's just a matter of names. If
different people had named them, they might have been called seas.

The ocean covers a large amount of space and is shared by many different places and countries. A sea, usually much smaller in size than an ocean, belongs to a certain area and is named so. Therefore, the ocean is shared by many and a sea is shared by few.

ocean are deeper than sea,and also ocean are bigger than sea.

Seas are smaller then Oceans

It's semantics really. When the oceans and seas were originally named, they didn't have the benefit of seeing the world on the scale that we now see it. So they gave it their best guess whether it was an ocean, sea, gulf, whatever. Really, it's just a name.

oceans are bigger than seas

seas divide countries oceans divide continents

THE DIFFERENCE IS
OCEAN IS LARGER IN SIZE COMPARED TO SEA
SEA IS WHEN A LAKE IS BECOME TOO LARGE WHILE OCEAN OCCURRED IN NATURAL

THE DIFFERENCE IS
OCEAN IS LARGER IN SIZE COMPARED TO SEA
SEA IS WHEN A LAKE IS BECOME TOO LARGE WHILE OCEAN OCCURRED IN NATURAL

The Ocean is a way better place to hide your bodies, i would only go to a sea as a last resort, both are just as good to drown a baby in though.

Sea is surrounded by Land and Land is surrounded by Ocean, both will have Beaches and salt water Example: Caspian sea, Aral sea and Indian Ocean.

Ocean are larger than seas.

http://en.wikipedia.org/wiki/Ocean
An ocean (from Greek Ὠκεανὸς, "okeanos" Oceanus[1]) is a major body of saline water, and a principal component of the hydrosphere. Approximately 71% of the Earth's surface (~3.6×108 km2
) is covered by ocean, a continuous body of water that is customarily divided into several principal oceans and smaller seas.

More than half of this area is over 3,000 metres (9,800 ft) deep. Average oceanic salinity is around 35 parts per thousand (‰) (3.5%), and nearly all seawater has a salinity in the range of 30 to 38 ‰. Scientists estimate that 230,000 marine species are currently known, but the total could be up to 10 times that number.

A sea generally refers to a large body of salt water, but the term is used in other contexts as well. Most commonly, the term refers to a large expanse of saline water connected with an ocean, and is commonly used as a synonym for ocean.[1] It is also used sometimes to describe a large saline lake that lacks a natural outlet, such as the Caspian Sea.

To be very definitive, it's hard to belive if there is any difference between ocean and sea. These are the terms used in relative sens. All is water filled the space it find as topographic low and is the continuity of one single mass of water body on the entire planet.