pecos river Pecos • pecs · · · Info · Definitions · Characters · · pecos river · · Text Common · · Latin · · Scripts 11 · · Length 4 · · Syllables Definitions · · · (noun) a tributary of the Rio Grande that flows southeastward from New Mexico through western Texas. Synonyms: Pecos, Pecos River. · · Noun Definition 1 Characters · · space U+0020 c latin small letter c U+0063 e latin small letter e U+0065 i latin small letter i U+0069 o latin small letter o U+006F p latin small letter p U+0070 r latin small letter r U+0072 s latin small letter s U+0073 v latin small letter v U+0076