The acronym MRTA stands for the Movimiento Revolucionario Túpac Amaru, a Marxist guerrilla organization that was active in Peru during the 1980s and early 1990s. In Spanish, "MRTA" translates to "Movimiento Revolucionario Túpac Amaru." There are a few potential synonyms for MRTA, depending on how one wishes to describe the group. Some possible options may include "Peruvian guerrilla group," "left-wing militants," or "Marxist insurgents." However, it is important to note that MRTA was a complex group with various ideological and political motivations, and no single term can accurately capture the entirety of their actions and beliefs.