base · noun C /beɪs/Full view
Nouns: base, basics, basis
Adjectives: baseless, basic
Verbs: base
Adverbs: basically
base (BOTTOM)
B2 the bottom part of something, or the part something rests on
Dictionary examples:

a crystal glass with a heavy base

At the base of the cliff was a rocky beach.

base (MILITARY)
B2 a place where a military service operates and people in that military service live
Dictionary examples:

an army/navy/air force base

an old military base

Learner example:

During the day you can visit all of our museums or schools or even the air force base, which is open from 9 o'clock. (First Certificate in English; B2; Portuguese)

base (MAIN PLACE)
C2 the main place where a person lives or works or where a business operates
Dictionary examples:

I spend a lot of time in Dallas, but Chicago is still my base.

Nice is an excellent base for exploring the French Riviera.

Learner example:

It also has a function as a base for the fishing industry. Being located [o]n the coast, our town's key industry is fishing. (Certificate of Proficiency in English; C2; Japanese)

base (MAIN PART)
C2 the most important part of something, from which other things can develop
Dictionary example:

a solid economic base

Learner example:

Apart from the economic base of tourism, there are other beneficial aspects to consider. (Certificate of Proficiency in English; C2; Portuguese)

base · verb /beɪs/
Nouns: base, basics, basis
Adjectives: baseless, basic
Verbs: base
Adverbs: basically
be based in/at
B2 to have a particular city, town, area, etc., as the main place where you live and work, or where you do business
Dictionary example:

He was based in South Carolina.

Learner example:

The name of the company is Lilley's Bookshop and it is based in Central London. (First Certificate in English; B2; Catalan)

base sth on sth
B1 If you base something on facts or ideas, you use those facts or ideas to develop it.
Dictionary example:

The film is based on a short story by Thomas Mann.

Learner example:

This is an exciting film based on the musical "The Phantom of the Opera". (Preliminary English Test; B1; Swiss German)

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