What is the Reports terminology of Special Fields?

Account.FullAddress:
This merges all the Account address fields to one field separated by commas and suppresses the Country if the Country is the User’s default country. Use this to save space on and improve the legibility of reports.
Account.MainContact:
This reports One Contact per Account. Accounts with no Contacts are not included. The Contact that is reported has Contact.DecisionMaker ticked, or where not indicated, the historically first created Contact in the Account.
Contact.FullAddress:
Similar to the Account.FullAddress, this concatenates all the Contact address fields to one field separated by commas unless the Contact address is blank, in which case it uses the Account address.
Contact.AddressLine, City, County/State, Postcode/Zip, Country:
Will report those fields unless the address is blank, in which case it will report the Account fields. Use the Contact address fields for mail merging to make sure that if a Contact has a local address it is picked up.
Opportunity.Value:
The total Value of the Opportunity, calculated as the sum of Quantity x Unit Value of the individual Opportunity Lines.
Opportunity.WeightedValue:
The total Weighted Value of the Opportunity, calculated as the sum of Quantity x Unit Value x Probability of the individual Opportunity Lines.
Custom Fields:
Will appear with their names if created.