The Chaco linguistic area is a linguistic area that includes various South American language families and isolates of the Chaco region of South America, in southern Brazil, southeastern Bolivia, Paraguay, Uruguay, and Argentina.
Common Chaco areal features include SVO word order and active-stative verb alignment.
[1] Campbell and Grondona (2012) list the following languages as part of the Chaco linguistic area.
Morris Swadesh includes Charruan along with Guaicuruan, Matacoan, and Mascoyan within his Macro-Mapuche stock.
Jolkesky (2016) suggests that Trumai has lexical similarities with the Macro-Mataguayo-Guaykuru and Tupian language families.