What do you think ? Is there any definition of DR & CR in accounting ??

Credit

an entry in the right hand column of an account; credits increase liability, income, and equity accounts and decrease asset and expense accounts

Debit

an entry in the left hand column of an account to record a debt; debits increase asset and expense accounts and decrease liability, income, and equity accounts

NOT DR & CR but specifically for DEBIT & CREDIT. DR & CR words are used during passing general entries,which indicates the nature of that transaction.

There is NO any proper definition of Debits & Credits in accounting terms, it is based on accounting equation that all expenses and assets are debited and all liabilities, capital  and revenue are credited:

Assets               =            Equities

Assets               =            Liabilities  + Capital (Owners)