upper respiratory tract upper respiratory infection • upper side · · · Info · Definitions · Characters · · upper respiratory tract · · Text Common · · Latin · · Scripts 23 · · Length 8 · · Syllables Definitions · · · (noun) the nose and throat and trachea. Synonyms: upper respiratory tract. · · Noun Definition 1 Characters · · space U+0020 a latin small letter a U+0061 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 t latin small letter t U+0074 u latin small letter u U+0075 y latin small letter y U+0079