What is Deferment?
Deferment meaning A temporary postponement of payment on a loan that is allowed under certain conditions and during which interest generally does not accrue on Direct Subsidized Loans, the subsidized portion of Direct Consolidation Loans, Subsidized Federal Stafford Loans, the subsidized portion of FFEL Consolidation Loans, and Federal Perkins Loans. All other federal student loans that are deferred will continue to accrue interest. Any unpaid interest that accrued during the deferment period may be added to the principal balance (capitalized) of the loan(s).
reference: Federal Student Aid – Glossary