huapahuac.

Headword: 
huapahuac.
Principal English Translation: 

something rough, harsh; something deadened, numb; a shrinkage of the nerves; or, something strong and firm (see Molina)

Orthographic Variants: 
uapahuac, oapaoac
IPAspelling: 
wɑpɑːwɑk
Alonso de Molina: 

uapauac. cosa aspera y crudia, o cosa enuarada y en cogida de neruios, o cosa fuerte y firme.
Alonso de Molina, Vocabulario en lengua castellana y mexicana y mexicana y castellana, 1571, part 2, Nahuatl to Spanish, f. 154v. col. 2. Thanks to Joe Campbell for providing the transcription.

Attestations from sources in English: 

oapaoac = rough (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), 95.

oapaoac = firm; oapactic (huapactic) = firm; oapacpâctic (huapacpactic) = very firm (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), 133.

themes: 
Health, Sickness, Wellness, Medicine
Sensory Perception (sound, smell, etc.)