Variation margin. This term means a payment made by a party to a futures, option, or swap to cover the current exposure arising from changes in the market value of the position since the trade was executed or the previous time the position was marked to market.
17 CFR § 1.3
Words used in the singular form in the rules and regulations in this chapter shall be deemed to import the plural and vice versa, as the context may require. The following terms, as used in the Commodity Exchange Act, or in the rules and regulations in this chapter, shall have the meanings hereby assigned to them, unless the context otherwise requires: