cocomotza.

Headword: 
cocomotza.
Principal English Translation: 

for a baby to savor its milk while nursing; or, to make a noise by stamping feet (see Molina)

IPAspelling: 
kokomotsɑ
Alonso de Molina: 

cocomotza. nino. (pret. oninococomotz.) paladear el niño quando mama.
cocomotza. nitla. (pret. onitlacocomotz.) hazer estruendo con los pies.
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: 

COCOMOTZ(A) vrefl,vt for a baby to make a smacking noise nursing at the breast; to make a clamour, clatter with one’s feet / paladear el niño cuando mama (M), hacer estruendo con los pies (M) [(1)Cf.74v]. See COMŌN(I).
Frances Karttunen, An Analytical Dictionary of Nahuatl (Norman: University of Oklahoma Press, 1992), 39.