Useful English Phrases About The Sea for Learners

Useful English Phrases About The Sea for Learners

The sea is a part of all of our lives – even when we live very far away from it! And it is common in English both idiomatically as well as an actual subject in itself!

(Here I am going to talk mostly about the sea as water… not so much about the animals in it or even about phrases about boats, and sailing that have come into modern language!)

We will look at the following categories

  • Difference between Sea and Ocean(Answer: There isn’t one really!)
  • Basic Words (waves, current, swell etc) & Collocations: (standard adjectives, verbs, prepositions) (eg not ‘large sea’)
  • Common expressions to describe events at sea (eg ‘to be swept away’)
  • Idiomatic and Representational language connected to the sea (eg ‘in deep water’)

Difference between 'Sea' and 'Ocean' (Answer: There isn’t one really!)

So the first thing is, what is the difference between a sea and an ocean? Well, there is no definite distinction. However, there are 2 general conventions, although there are exceptions to both.

1 OCEAN in General: “An ocean does not touch the coastline, it exists where there is unending water.” (Exception(s): there are many exceptions, for example most of the United States coast is on either the Pacific Ocean or the Atlantic Ocean – in fact many of the world’s coastlines touch the ocean.)

2 SEA in General: “The sea is an area of water that touches the coast, and is mostly bordered by land” (Exception(s): The most notable exception to this is the Sargasso Sea which is a large area of water completely within the Atlantic Ocean!)

So in practical terms, much as we must learn the names of countries we have to learn the names of seas and oceans! However, the term ‘seas’ (even by the United Nations [Wikipedia Sea: Definition]) can refer to all the open water around the world. And a cup of the water from an ocean can always be called ‘seawater’.

Basic Words

Here are some basic words about the sea, please note that there are many words connected to boats and ships – I am planning on doing another post soon about those types of words too! But for now here are some of the most important words in relation to the sea.

42+ common words about the sea and some notes on usage!

Bay - an area on the coast where the sea is surrounded on three sides, can be many kilometres wide!

Body of water - an expression used to describe an area of the earth’s surface that is covered in water.

To break – this is when a wave ‘falls over’ - especially near the coast – important for surfers!

Coast - this is a general term for the area of land next to/near the sea. It is probably the most common of similar phrases [compare to: coastline, shore, seaside etc].

Standard collocations include:

  • On the coast: “I have a house on the coast”.

  • Off the coast: “There is a fantastic coral reef just off the coast near here.”

  • Along the coast: “We went along the coast in our canoes for about 20 minutes.”

  • Coast to coast: “One day I would love to drive across the whole of America, from coast to coast.”
    [Note that this describes a journey on land!]

Coastline – the actual border between sea and land, and the shape it produces from above.

Continental shelf – the area of the earth’s crust near the coast of a continent that is not particularly deep.

Coral reef – A reef is an area of sand or rocks very near the surface of the sea, often dangerous to boats. A coral reef is a reef made of hard organic matter produced by certain sea animals, can be used in jewellery.

To crash - a verb used to describe when a wave hits something with force,“waves crashed against the rocks”.

Crest of a wave – top of the wave.

Current – the movement of a section of the sea in a particular direction, often moving very quickly and dangerously for swimmers

  • Against the current: “It was very tiring swimming against the current.”

  • With the current: “The boat drifted away with the current.”

  • Strong current: “The strong current took us away from the shore.”

Depth - the distance from the surface of the sea downwards

  • Depth of: “The divers went to a depth of 100 metres.”

The depths - the very deepest/ lowest parts of the sea, “The Titanic sank to the depths of the ocean.”

Glacier – a large amount of ice that moves slowly, see Iceberg

Gulf – a very large area of sea surrounded on three sides by a coast, while a bay may be a few kilometres wide, a gulf (eg the Gulf of Mexico) can be hundreds of kilometres wide!

Iceberg – a large amount of ice that is moving freely and floating in the sea.

  • to hit an iceberg: “Ships that hit an iceberg can sink.”

Longshore drift – the movement of sand, stones by the sea along the coast. “That bank of sand was caused by longshore drift.” {a bank of sand is a hill of sand in the sea.}

Marine – an adjective to mean related to the sea, or sea transport. For example, marine biologist, marine traffic, marine life, marine soldier… often simply referred to ‘a marine’.

Maritime – a (formal) adjective to describe human activity at sea. For example, maritime museum, maritime power, maritime nation.

Oceanography – the scientific study of the sea

Offshore - away from or at a distance from the coast “I work on an offshore platform.” The opposite is “onshore”. An 'offshore wind' means wind going away from the coast, while 'onshore winds' means wind coming from the sea to the land.

Oil platform / Oil rig – structures built offshore in order to get oil from the seabed.


Also: Seas: "Seas" indicate not a particular sea or ocean, but the 'seas of the world' in general.

  • He came from across the sea (THAT sea).

  • He came from across the seas ( = from far away).

Common Adjectives
  • Calm: “The sea was very calm today, no one got seasick.”

  • Smooth: “Look how smooth the sea is today!”

  • Choppy: “The choppy sea made the journey horrible.”

  • Rough: “The sea was rough and everyone was scared.”

  • Deep: “The sea is very deep in that area.”

  • Shallow: “In shallow seas there can be problems with reefs.”

  • Open: “I love staring out at the open sea.”

Common Verbs
  • To Cross: “It took 2 weeks to cross the sea.”

  • To rise: “When the tide is high, it means the sea has risen.”

  • At sea: “I work at sea 6 months of the year.”

  • Across the sea: “One day I want to go across the sea.”

  • By (the) sea: “They have a house by the sea.”

  • In the sea: “Sharks live in the sea.”

The Seabed – the floor or bottom of the sea/ocean.

  • To lie on the seabed: “The shipwreck lay on the seabed.”

The Seafloor – a synonym of the seabed (the floor or bottom of the sea/ocean).

Seagoing – to describe a boat, ship etc that has been designed to travel on the sea/ocean (and not rivers, coasts, lakes etc).

Sea lane – a area of the sea often used by ships (so it can require extra attention to pass through).

Sea level - the general level of water around the world

  • Above sea level: “Our city is 50 metres above sea level.”

Seasick – to vomit, or feel unwell, caused by the movement of the boat/ship you are own.

  • To suffer from seasickness: “I hate going on the ferry because I suffer from seasickness.”

The Seaside – a part of the coast that is typically differentiated by human recreational activity – especially holidays, shops/bars etc.

Sea wall – a wall built into the sea to protect the coast from erosion or near a port/harbour to protect boats/ships.

Seawater – the water from the sea, on average has 35 grams of salt for every litre. An opposite term might be ‘freshwater’ - this is water found in rivers and lakes.

Seaweed – a green, or browny, or even red plant that grows in the sea.

Shore – is a general term used to describe the border between water and land, this includes seas, rivers, lakes etc. Compared to coast (which is only for large bodies of water) shore can also be used for much smaller areas near water.

Swell – when larger areas of the sea move as a single mass up and down. Sometimes you go down so far you can no longer see the horizon!

Tide – the twice daily variation in local areas of the sea level, caused by the moon

  • High tide: At high tide the water reaches up to the wall.

  • Low tide: When there is low tide, we go out to get crabs.

  • The tide is in = high tide

  • The tide is out = low tide

Tide pool – a small pool of water left behind when the tide goes out.

Trench – a very deep valley, possibly kilometres deep, in the seabed. Also “sea/ ocean trench”.

Tsunami – an incredibly large and destructive wave

Underwater – to dive underwater means to dive below the surface of the water.

Wave – as energy moves through the sea some of the water goes up, causing these little ‘hills’ of water – waves!

  • To break: “Waves break as they reach the coast.”

Common expressions to describe events at sea

As well as many of the expressions listed above, here are some terms connected to the sea. Note that I have excluded the many many many phrases that we use to describe situations actually on ships and boats!

To work at sea : this expression can be used for someone who works on ships or boats, but also someone who might work off-shore, on an oil rig for example. For example, “My uncle worked at sea for many years.”

To be swept away (by the current): This occurs when a person or object enters (or falls) into the sea and the current moves them away very quickly. For example: “The man who fell overboard was quickly swept away by the current.”

To catch a wave: used particularly by surfers this verb means to position yourself on the crest of a wave and use its energy to move you forward very quickly – lot’s of fun if you are surfing!

To be lost at sea: this can be used simply to mean a person who has no idea where they are at sea. But it is also used euphemistically to mean that the person died at sea and so was ‘lost’.

Run away to sea – especially of a young person / to become a sailor.

The Seven Seas – is a phrase from ancient times to denote all the seas in the world, not used nowadays as a technical ‘truth’.

Idiomatic and Representational language connected to the sea

There are a lot of expressions that use the sea to describe our daily life. I have put some of the most common here:

A drop in the ocean: This means a small part of a bigger problem or situation.

“We worked very hard but it was just a drop in the ocean, there was too much to do.”

Plain sailing: When things go very well, or very easily.

“We drove here yesterday in the car, there were no problems – it was all plain sailing.”

Rock the boat: To disturb a calm or settled situation, to upset people.

“Please don’t rock the boat – just ignore their provocations.”

To make waves: To make an impact and get noticed

“That new artist is really making waves in the local art scene.”

Flotsam (and jetsam): Literally a word to describe the broken ‘rubbish’ that can be seen floating in the sea. Figuratively it is used to describe people/things which are considered superfluous, unimportant or useless.

“The homeless people were like the flotsam (and jetsam) of the city.”

Get into deep water: To get into trouble.

“I got into some deep water when I didn’t come home that night.”

Davy Jones’ Locker: An idiom for the bottom of the sea and the last resting place of drowned sailors.

“In Pirates of the Caribbean they are always talking about Davy Jones’ Locker.”

Dead in the water: It means that ‘it’ has failed and cannot be brought back to life.

“After three months, the project was dead in the water. No clients, no cash.”

To dip your toe into the water: To try something new, often with little risk.

“I did the free trial at the gym just to dip my toe in the water and see if I liked it.”

The tide is turning: That the general forces around a situation are changing/reversing direction.

“And finally after all our hard work the tide started to turn and things got better!”

To be all at sea: To not have an idea what you are doing, be confused.

“I started my new job, but I understood nothing – I was all at sea for about 3 months!”

The coast is clear: When there is no danger that anyone can see or stop you doing something.

“As soon as the coast is clear we will go in and rob the bank.”
“She’s left her boyfriend, I think the coast is clear for you.”

To ride the crest of a wave: To be on top of a positive momentum.

“After the surprise hit film he did, he has been riding the crest of a wave with a series of great roles.”

A sea of (faces, people..): A lot of individual things that create a feeling of a single mass.

“I got on stage and all I could see was a sea of faces looking at me.”

I hope that these phrases have been useful and interesting! Adam

Here are some links that could be of interest!

Check out: Useful Phrases for Luck in English for Learners