water · noun U /ˈwɔːt̬.ər/Full view
Nouns: water
Adjectives: underwater, waterproof, watery
Verbs: water
Adverbs: underwater
water (LIQUID)
A1 the clear liquid that falls from the sky as rain and is necessary for animal and plant life
Dictionary examples:

hot/cold water

a bottle/drink/glass of water

bottled/mineral/tap water

a drop of water

Learner example:

You have to bring some food, and a lot of water. (Key English Test; A2; Spanish)

water (OCEAN/LAKE)
A2 an area of water, such as the ocean, a lake, or a swimming pool
Dictionary examples:

The water's much warmer today - are you coming for a swim?

Dad, I swam a whole length of the pool under water!

Learner example:

There are a lot of beautiful beaches with clean water. (Key English Test; A2; Portuguese)

be (like) water off a duck's back
C2 If criticisms, insults, etc., are like water off a duck's back to you, they do not affect you at all.
Dictionary example:

She calls him lazy and useless, but it's like water off a duck's back.

Learner example:

The main lesson I have learned is by looking at some people who have lived alone for most of their life and faced with neither contradiction nor argument, they stay in their ivory tower, so sure of their opinions that whatever you say is like water off a duck's back. (Certificate of Proficiency in English; C2; French)

running water
C1 If a building has running water, water comes into it through pipes.
Dictionary example:

The summer homes on the island have no running water.

Learner example:

It is hilarious to think that at the same time people in [the] north of Europe were still living a primitive and uncivilized life not even able to invent an axe, the Romans managed to install running water in their huge houses. (Certificate in Advanced English; C1; Danish)

not hold water
C2 If you say that an argument doesn't hold water, you mean that it can't be true.
Dictionary example:

The jury convicted her because her story just didn’t hold water.

Learner example:

It remains to us to prove that the opinions of some scientists are far-fetched and don't hold water. (Certificate of Proficiency in English; C2; Greek)

fresh water
C2 water from lakes, rivers, etc. that has no salt in it
Dictionary example:

These fish live in fresh water.

Learner example:

You find stunning white beaches, clear, fresh water lakes, isolated tropic islands, reef, rainforests, buzzing cities, challenging mountain range, bush, outback - and the desert. (Certificate of Proficiency in English; C2; Danish)

keep your head above water
C2 to have just enough money to live or to continue a business
Dictionary example:

With extra income from private sponsorship, the club is just about managing to keep its head above water.

Learner example:

I also started to reali[z]e how much she had on her plate, how very little help she had and how, at times, she had to struggle just like me to keep her head above water. (Certificate of Proficiency in English; C2; Dutch)

water · verb /ˈwɔːt̬.ər/
Nouns: water
Adjectives: underwater, waterproof, watery
Verbs: water
Adverbs: underwater
water (PLANTS)
B2 T to pour water on to plants or the soil that they are growing in
Dictionary example:

I asked my neighbor to water the plants while I'm away.

Learner example:

I can spend a lot of time digging, pulling up weeds, watering my plants and pruning the bushes and so on. (First Certificate in English; B2; Polish)

water (MOUTH)
C2 I If food makes your mouth water, it makes you want to eat it, sometimes making your mouth produce liquid.
Dictionary example:

The smells from the kitchen are making my mouth water.

Cambridge logo