cocotli.

Headword: 
cocotli.
Principal English Translation: 

tube, esophagus, windpipe, throat; urethra (see also our entry for cocotli meaning turtledove or perhaps "little one")

Orthographic Variants: 
cocohtli
IPAspelling: 
koːkohtɬi
Alonso de Molina: 

cocotli. garguero.
Alonso de Molina, Vocabulario en lengua castellana y mexicana y mexicana y castellana, 1571, part 2, Nahuatl to Spanish, f. 23v. col. 2. Thanks to Joe Campbell for providing the transcription.

Frances Karttunen: 

CŌCOH-TLI throat, windpipe / garguero (M) cuello, (T) [(7)Tp.121,147]. M provides the absolutive suffix, the –TLI form of which indicates a stem-final glottal stop, glottal stop, T characteristically lacks the internal glottal stop and moreover has reflexes of long vowels in both syllables. CŌCOH-TLI dove, mourning dove / tortoa (M) tórtola mexicana (R) [(1)Rp.77,(1)Tp.121,(3)Xp.33]. R attests the stemfinal glottal stop and absolutive suffix, while T’s and X`s CŌCOTETZIN lacks the glottal stop, but attests the long vowel in the firts syllable. This is apparently homophonous with CŌCOH-TLI ‘throat.’ For a similar case, see COPĀCTECOLŌ-TL.
Frances Karttunen, An Analytical Dictionary of Nahuatl (Norman: University of Oklahoma Press, 1992), 38.

Attestations from sources in English: 

cocôtli = urethra; tococôio = our urethra; meltecujnja = one's urethra is intermittently obstructed; textemj = it fills with fine-textured material (central Mexico, sixteenth century)
Fr. Bernardino de Sahagún, Florentine Codex: General History of the Things of New Spain; Book 10 -- The People, No. 14, Part 11, eds. and transl. Arthur J. O. Anderson and Charles E. Dibble (Santa Fe and Salt Lake City: School of American Research and the University of Utah, 1961), 132.

cocotl = esophagus;
tlatolhoaztli = gullet;
tlatololoni = the swallower;
vncãan mopetzcoa, in tlaqualali = there the food is slipped down; tlatoloa = it swallows;
tlatopeoa = it forces [down];
tlapetztoloa = it swallows things smoothly (central Mexico, sixteenth century)
Fr. Bernardino de Sahagún, Florentine Codex: General History of the Things of New Spain; Book 10 -- The People, No. 14, Part 11, eds. and transl. Arthur J. O. Anderson and Charles E. Dibble (Santa Fe and Salt Lake City: School of American Research and the University of Utah, 1961), 108.

themes: 
Anatomy