Varaxian LM-7 was supposedly a type of biogenic weapon, claimed by Quark to be in the experimental stage as of 2373.

During his brief stint as one of Hagath's associates, Quark claimed he had obtained a supply of Varaxian LM-7 in lieu of a mutagenic retrovirus for the Regent of Palamar. In fact, the shipment was a setup to bring the Regent in contact with his nemesis, General Nassuc. (DS9: "Business as Usual")

"Varaxian LM-7" may have been Quark's invention for the purposes of his scheme, as Hagath had never heard of it.
According to the script, this weapon's name was pronounced as "vuh-RAX-ee-un". [1]