rec‧og‧nize S1 W1 (also recognise British English) /ˈrekəɡnaɪz, ˈrekən-/ verb [transitive]
[Word Family: verb: recognize; noun: recognition; adverb: recognizably; adjective: recognizable ≠ unrecognizable]
[Date: 1400-1500; Language: Old French; Origin: reconoistre, from Latin recognoscere, from cognoscere 'to know']

1. [not in progressive] to know who someone is or what something is, because you have seen, heard, experienced, or learned about them in the past:
I didn’t recognize you in your uniform.
It was malaria, but Dr Lee hadn’t recognized the symptoms.

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In everyday English, people often say that they know (that) it is someone or something rather than say they recognize them:
I knew it was her by the hat she was wearing.

2. to officially accept that an organization, government, document etc has legal or official authority:
British medical qualifications are recognized in Canada.
recognize something as something
The World Health Organization has recognized alcoholism as a disease since 1951.

3. to accept or admit that something is true
recognize (that)
One must recognise that homesickness is natural.
recognize what/how/who etc
It is important to recognize how little we know about this disease.

4. [usually in passive] if something is recognized by people, they realize that it is important or very good:
Alexander tried to get his work recognized by the medical profession.
be recognized as something
Lawrence’s novel was eventually recognized as a work of genius.
a recognized authority on Roman pottery

5. to officially and publicly thank someone for something they have done, by giving them a special honour:
He was recognized for having saved many lives.
—recognizable /ˈrekəɡnaɪzəbəl, -kən- ˌrekəɡˈnaɪ-/ adjective:
His face was instantly recognizable.
—recognizably adverb

[TahlilGaran] Dictionary of Contemporary English ▲