This element for "Air" or "Breath" (Ecatl) has the diagnostics that point to the divine or sacred force or spirit associated with the wind [eheca(tl)]. It has been carved from the compound glyph for the personal name Ecacoacatl. It shows what appears to be the head of a man in profile (facing to the viewer's right) with a thick black stripe running vertically across the side of his face. A bird's beak protrudes from his mouth. It looks something like a duck bill.
The gloss here gives "Ecatl," but the visuals suggest "Ehecatl." A great many glyphs in this collection start with Eca- when one might expect Eheca-. We are preserving the proclivity of the gloss for Eca-, while also pointing to the likelihood of an unintentional oral abbreviation of Eheca- to Eca-.
The black line (face paint?) across this man's face is a diagnostic for Ehecatl. The lack of reduplication of the first syllable in the man's name is not unusual. Ecatl can mean air, and ehecatl is the usual way of writing wind. Wind has a notable importance in Nahua religion. It was a day sign in the calendar, which meant it ended up as a personal name for many people.
viento, aliento, aires
eca(tl), air/breath, https://nahuatl.wired-humanities.org/content/ecatl
eheca(tl)/Ehecatl, wind or the divine force or spirit of the wind, https://nahuatl.wired-humanities.org/content/ehecatl
Matrícula de Huexotzinco, folio 485v, World Digital Library, https://www.loc.gov/resource/gdcwdl.wdl_15282/?sp=45&st=image
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