Coahuilteco was one of the Pakawan languages that was spoken in southern Texas (United States) and northeastern Coahuila (Mexico).

Coahuilteco was grouped in an eponymous Coahuiltecan family by John Wesley Powell in 1891, later expanded by additional proposed members by e.g. Edward Sapir.

Manaster Ramer (1996) argues Powell's original more narrow Coahuiltecan grouping is sound, renaming it Pakawan in distinction from the later more expanded proposal.

[3] Based primarily on study of one 88-page document, Fray Bartolomé García's 1760 Manual para administrar los santos sacramentos de penitencia, eucharistia, extrema-uncion, y matrimonio: dar gracias despues de comulgar, y ayudar a bien morir, Troike describes two of Coahuilteco's less common syntactic traits: subject-object concord and center-embedding relative clauses.

One example of such a center-embedded relative clause is the following: saxpame·sinspinapsa·iyou[xami·n(OBJ)ei-Obj xa-p-xo·]2-sub-knowtupa·-nDEM-1Csaxpame· pinapsa·i [xami·n ei-Obj xa-p-xo·] tupa·-nsins you (OBJ) {} 2-sub-know DEM-1C‘the sins (which) you know’The Coahuilteco text studied by Troike also has examples of two levels of embedding of relative clauses, as in the following example (Troike 2015:138): pi·lampeopleapšap’a·kanigood.PL[ei-SUBJ pi·nwakta·jthings[DiosGod(∅)(DEM)pil’ta·jpronja-pa-ta·nko]3-sub-commandtuče·-tDEM-3Ca-p-awa·y]3-sub-do.PLtupa·-tDEM-3Cpi·lam apšap’a·kani [ei-SUBJ pi·nwakta·j [Dios (∅) pil’ta·j a-pa-ta·nko] tuče·-t a-p-awa·y] tupa·-tpeople good.PL {} things God (DEM) pronj 3-sub-command DEM-3C 3-sub-do.PL DEM-3C‘(He will carry to heaven) the good people [who do the things [that God commands]]’.