Principal English Translation: 

the toe(s) or ball(s) of the foot (see Molina and Sahagún)

Alonso de Molina: 

quetzilpaina. ni. (pret. oniquetzilpain.) andar apriesa, o correr sobre las puntas delos pies.
Alonso de Molina, Vocabulario en lengua castellana y mexicana y mexicana y castellana, 1571, part 2, Nahuatl to Spanish, f. 89r. col. 2. Thanks to Joe Campbell for providing the transcription.

Attestations from sources in English: 

ioan conaaqujlia iancujc in jpoçolcac xoxoctic in jquequetzil = and they put on him his new foam sandals with green toes (central Mexico, sixteenth century)
Fr. Bernardino de Sahagún, Florentine Codex: General History of the Things of New Spain; Book 8 -- Kings and Lords, no. 14, Part IX, 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, 1951), 62.