citlalcuitlatl.

Headword: 
citlalcuitlatl.
Principal English Translation: 

obsidian; obsidian was viewed as star excrement that turned into worms that invaded animals (see Karttunen)

Orthographic Variants: 
cītlalcuitlatl
IPAspelling: 
siːtɬɑlkwitɬɑtɬ
Frances Karttunen: 

CĪTLALCUITL(A)-TL obsidian / la suciedad de estrella, gusanos en la tierra (Z) [(1)Z p. 203]. Obsidian is known in Spanish in some areas by the apparent loan translation 'caca de estrella,' but another explanation of Z`s rather opaque gloss is the belief reported in the Florentine Codex that falling stars turn into worms that invaded animals (Bk.7, P.13). See CĪTLAL-IN, CUITL(A)-TL.
Frances Karttunen, An Analytical Dictionary of Nahuatl (Norman: University of Oklahoma Press, 1992), 35.