cecepatic.

Headword: 
cecepatic.
Principal English Translation: 

something very cold; or, as a metaphor, something startling (see Molina and Karttunen)

Orthographic Variants: 
cecepahtic
IPAspelling: 
seseːpɑhtik
Alonso de Molina: 

cecepatic. cosa muy fria. et per metaphoram. cosa muy espantable.
Alonso de Molina, Vocabulario en lengua castellana y mexicana y mexicana y castellana, 1571, part 2, Nahuatl to Spanish, f. 15v. col. 1. Thanks to Joe Campbell for providing the transcription.

Frances Karttunen: 

CECĒPAHTIC something very cold, something that gives one the chills / cosa muy fria... cosa muy espantable (M) [(1)Zp.166]. The long vowel of the second syllable is questionable. See CE-TL, CEPŌHUA.
Frances Karttunen, An Analytical Dictionary of Nahuatl (Norman: University of Oklahoma Press, 1992), 27.

Attestations from sources in English: 

cecepatic = cold (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.