is there a way to map between the field name in the report meta data  to salesforce objects?

I'm using the Metadata Api to retrive metadata about a report

the result is something like this

<?xml version="1.0" encoding="UTF-8"?>
<Report xmlns="http://soap.sforce.com/2006/04/metadata">
    <columns>
        <field>SALUTATION</field>
    </columns>
    <columns>
        <field>FIRST_NAME</field>
    </columns>
    <columns>
        <field>LAST_NAME</field>
    </columns>
    <columns>
        <field>TITLE</field>
    </columns>
    <columns>
        <field>ADDRESS2_STREET</field>
    </columns>
    <columns>
        <field>ADDRESS2_CITY</field>
    </columns>
    <columns>
        <field>ADDRESS2_STATE</field>
    </columns>
    <columns>
        <field>ADDRESS2_ZIP</field>
    </columns>
    <columns>
        <field>ADDRESS2_COUNTRY</field>
    </columns>
    <columns>
        <field>PHONE1</field>
    </columns>
    <columns>
        <field>PHONE3</field>
    </columns>
    <columns>
        <field>PHONE2</field>
    </columns>
    <columns>
        <field>EMAIL</field>
    </columns>
    <columns>
        <field>OWNER_FULL_NAME</field>
    </columns>
    <columns>
        <field>ACCOUNT.NAME</field>
    </columns>
    <columns>
        <aggregateTypes>Sum</aggregateTypes>
        <field>SALES</field>
    </columns>
    <columns>
        <field>Account.Active__c</field>
    </columns>
    <filter>
        <criteriaItems>
            <column>SALES</column>
            <operator>greaterThan</operator>
            <value>40000000</value>
        </criteriaItems>
    </filter>
    <format>Tabular</format>
    <name>muly1</name>
    <reportType>ContactList</reportType>
    <scope>my</scope>
    <showDetails>true</showDetails>
    <timeFrameFilter>
        <dateColumn>CREATED_DATE</dateColumn>
        <interval>INTERVAL_CUSTOM</interval>
        <startDate>2008-08-05</startDate>
    </timeFrameFilter>
</Report>

what is ContactList?

what is ADDRESS2_STREET?