world · noun /wɜːld/Full view
Nouns: world, underworld
Adjectives: worldly, worldwide, world
Adverbs: worldwide
world (THE EARTH)
A1 no plural the Earth and all the people, places and things on it
Dictionary examples:

She's travelled all over the world.

News of the disaster shocked the whole world.

We live in a changing world.

Learner example:

I like travel[l]ing and discovering new place[s] [i]n the world. (Skills for Life (Entry 1); A1; Serbian)

your world
A2 your life and experiences
Dictionary example:

His whole world fell apart when she left.

Learner example:

I like this room because it's "my world" and because it is very big. (Key English Test; A2; Italian)

world (GROUP)
B1 C usually no plural the people and things that are involved in a particular activity or subject
Dictionary examples:

the entertainment world

the world of politics

Learner example:

Well, as you know, I'm not very interested in the fashion world, so I rarely spend much time shopping for clothes. (Preliminary English Test; B1; Portuguese)

(have) the best of both worlds
C1 to have the advantages of two different situations
Dictionary example:

Living in the country and working in the city you have the best of both worlds.

Learner example:

Only those that can afford to live in the suburban areas can combine the best of both worlds and they tend to be rather affluent. (Certificate of Proficiency in English; C2; Greek)

be out of this world
C2 to be of extremely good quality
Dictionary example:

Their chocolate cake is just out of this world!

Learner example:

The dessert trays are out of this world. (Certificate of Proficiency in English; C2; Swedish)

do sb a/the world of good
C2 to make someone feel much happier or healthier
Dictionary example:

That swim has done me a world of good.

Learner example:

I feel a year abroad would do her a world of good in letting her care for children, learn to speak English properly, and see life from different aspects. (Certificate in Advanced English; C1; Swedish)

not be the end of the world
C2 If something is not the end of the world, it will not cause very serious problems.
Dictionary example:

It won't be the end of the world if I don't get the job.

be/feel on top of the world
C2 to be very happy
Dictionary example:

I had just won a major tournament and I was feeling on top of the world.

Learner example:

I felt like I was on top of the world and nothing could take that happiness from me. (Certificate of Proficiency in English; C2; Greek)

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