to sieve or sift something for someone else; or, to shake out the clothing of someone (see Molina)
IPAspelling:
tsetselwiɑː
Alonso de Molina:
tzetzelhuia. nitetla. (pret. onitetlatzetzelhui.) cerner algo a otro, o sacudir le la ropa. Alonso de Molina, Vocabulario en lengua castellana y mexicana y mexicana y castellana, 1571, part 2, Nahuatl to Spanish, f. 152r. col. 1. Thanks to Joe Campbell for providing the transcription.
Frances Karttunen:
TZETZELHUIĀ vt to shake out or beat something for someone / cerner algo a otro o sacudirle la ropa (M) applic. TZETZELOĀ. Frances Karttunen, An Analytical Dictionary of Nahuatl (Norman: University of Oklahoma Press, 1992), 311.