It's not an acronym, it's the word "lore:" to quote Urban Dictionary, "the collective history and the sum of all knowledge available about a certain fantasy or sci-fi universe." Lore mods are designed to fit into the lore of the GTA HD universe (which includes IV, EFLC, and V). For instance, a lore texture is one for a department that fits into the V world (whether that's a real department like the LSPD or an invented one like the Blaine County Sheriff or Del Perro PD). A lore model is one that's generally based on Rockstar's vehicles, normally coming from IV or V, not real life cars. Lore models might be different from any car in the stock game, like some of Lt. Caine's creations, but they're critically *not* recreations of real vehicles. If you combine the back of the V ambulance with the cab of the Bison, that's different from the ambulance Rockstar created (which uses a Burrito cab), but it's still lore because it's based on GTA cars. If you converted a model from Max Payne 3, that'd generally be considered lore because MP3 also doesn't use real-life cars. If you converted a Dodge Ram cab from a racing game, that'd be a real-life vehicle and so not lore.