ecamalacotl.

Headword: 
ecamalacotl.
Principal English Translation: 

a whirlwind, tornado (see Molina); dustdevil (see Karttunen); also, attested as a pesonal name (male)

IPAspelling: 
ehkɑmɑlɑkoːtɬ
Alonso de Molina: 

ecamalacotl. remolino de viento.
Alonso de Molina, Vocabulario en lengua castellana y mexicana y mexicana y castellana, 1571, part 2, Nahuatl to Spanish, f. 28r. col. 1. Thanks to Joe Campbell for providing the transcription.

Frances Karttunen: 

EHCAMALACŌ-TL dust devil / remolinito (T) [(1)Tp.249]. The first element of this seems to have lost a syllable, and the final syllable has the reflex of Ō instead of expected A. See EHĒCA-TL, MALACA-TL.
Frances Karttunen, An Analytical Dictionary of Nahuatl (Norman: University of Oklahoma Press, 1992), 75.

Attestations from sources in English: 

Auh no yquac hecamalacotl moquetz ynicpac tlaltepehualli yn iglesia mayor caltitlan yuhqui xixitomoni yhuan yuhqui matlequiquiztli ye huehuetzi ynic conittaqueue tlaca yuhqui cacamachallohua tlalli auh yn iquac ye hualtemo hecamalacotl niman quitoque in castilteca ca ye quiça yn Motecuhçoma. (ADJB, f. 56v) = A whirlwind rose from the mound of dirt next to the main church. There was a flash of lightning and a sound like great gunfire. The people saw the jaws of the earth opening. As the wind died down, the Castilians were saying that Moteuczoma was emerging.
Ezequiel G. Stear, Nahua Horizons: Writing, Persuasion, and Futurities in Colonial Mexico (Tucson: University of Arizona Press, 2025), 141, citing Anales de Juan Bautista, 1582, f. 56v.

A person of the Nahua nobility named Huiznahuatl Ecamalacotl was sentenced for adultery and executed by stoning in front of a large crowd, according to the Florentine Codex.
Pilar Máynez, El calepino de Sahagún: un acercamiento (México: Universidad Nacional Autónoma de México, 2002), 130. She cites Book 8, fol. 27, 277 recto.

At least two names in the Matrícula de Huexotzinco are Ecamalacotl. See one here: https://aztecglyphs.wired-humanities.org/content/ecamalacotl-mh497r In this one and another, the ecamalcotl seems to be an apparatus that spins in the wind.

mjn hecamalacotl = Martín Ecamalacotl; elsewhere spelled: mjn hecamalacatl = Martín Ecamalcatl (It is not clear if this is the same name, given the final a and the name glyph having a spindle in the midst of wind.) (Tepetlaoztoc, sixteenth century)
Barbara J. Williams and H. R. Harvey, The Códice de Santa María Asunción: Facsimile and Commentary: Households and Lands in Sixteenth-Century Tepetlaoztoc (Salt Lake City: University of Utah Press, 1997), 86–87, 120–121, 122.