contact

I UK [ˈkɒntækt] / US [ˈkɑnˌtækt] noun
Word forms "contact":
singular contact plural contacts
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Get it right: contact:

When contact means "communication between people, countries, or organizations", it is usually an uncountable noun, so ▪  it is hardly ever used in the plural ▪  it never comes after a or a number
Wrong: They live in an isolated place and have no contacts with the outside world.
Right: They live in an isolated place and have no contact with the outside world.
Wrong: You can only get a feel for the language by having a constant contact with native English speakers.
Right: You can only get a feel for the language by having constant contact with native English speakers.  
Contact can also be a countable noun when it means "someone you know who can help you": She used to teach in Japan, and she has a lot of useful contacts in universities there.

1)

a) [uncountable] communication between people, countries, or organizations either by talking or writing

contact between:

There has been no direct contact between the two sides in the dispute.

contact with:

Jury members must avoid contact with the defendants and their families.

have contact:

He is no longer allowed to have any contact with his children.

be in (close/regular) contact:

The school and other care organizations have been in close contact.

get/keep/stay in contact:

Do you and Jo still keep in contact?

come into contact:

In Paris she came into contact with other young writers.

put someone in contact:

I asked her if she could put me in contact with a good piano teacher.

make contact:

I've been calling him for weeks but I still haven't made contact.

lose contact:

I have lost contact with most of my university friends.

bring someone into contact:

Our work brings us into contact every day.

b) [uncountable] if you have contact with a new idea or way of life, you learn about it by communicating with other people

These people have had very little contact with the modern world.

•

Collocations:
Verbs frequently used with contact as the object ▪  avoid, establish, have, initiate, lose, maintain, make, renew, resume, sever

2) [uncountable] a situation in which people or things touch each other

The disease is spread through sexual contact.

on contact with:

The chemicals become activated on contact with soil.

come into contact (with):

Make sure the wires do not come into contact with water.

3) [countable] someone you know who can help you, for example by finding work for you or giving you information

I'll talk to one of my contacts in the software business.

4) [countable] physics a place where two electrical conductors meet and where electric current passes between them

5) [countable] informal a contact lens

II UK [ˈkɒntækt] / US [ˈkɑnˌtækt] verb [transitive]
Word forms "contact":
present tense I/you/we/they contact he/she/it contacts present participle contacting past tense contacted past participle contacted
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to write to someone or talk to them on the telephone

Anyone with any information about the incident should contact the police.

You can always contact me on my home number.

His staff were unable to contact him by telephone.

III UK [ˈkɒntækt] / US [ˈkɑnˌtækt] adjective [only before noun]

1) a contact address or telephone number is one that people can use to write to you or talk to you

Please give your name, address, and an emergency contact number.

2) having an effect when one thing touches another

a contact explosive/weedkiller