1875, originally a legal term for "authorization to a debtor to postpone payment," from neut. of L.L. moratorius "tending to delay," from L. morari "to delay," from mora "pause, delay," originally "standing there thinking." The word didn't come out of italics until 1914. General sense of "a postponement, deliberate temporary suspension" is first recorded 1932.
A period of delay agreed to by parties to a dispute or parties who are negotiating. A moratorium may also be an authorized delay in the repayment of a loan, especially by a nation (as in a moratorium on war debts).