The loan amount refers to the amount of money the borrower has legally promised to repay to the lender.
While the total loan amount is the total amount of money borrowed from a lender at the point of loan closing, it refers to the total outstanding due at any point in time when it is referenced during the term of the loan.
For example, if a borrower has taken up a $100,000 mortgage for 30 years, when the loan amount is looked up on the 5 year, the loan amount refers to the outstanding loan balance at that point in time. Which might be $75,000.
For example, a $100,000 loan with 1 point financing would result in a total original loan amount of $101,000. The amortization will then be based on $101,000 rather than $100,000.