to recognize somebody/something and be able to say who or what they are

First of all we must identify the problem areas.

Scientists have identified the gene responsible for the disease.

As yet they have not identified a buyer for the company.

to identify a need/factor/source/cause

They are trying to identify what is wrong with the present system.

to make it possible to recognize who or what somebody/something is

In many cases, the clothes people wear identify them as belonging to a particular social class.

a serial number that uniquely identifies the disk

LEARNit Dictionary