to not leave anything, or to buy all of what is being sold (see Molina)
IPAspelling:
sentokɑ
Alonso de Molina:
centoca. nitla. (pret. onitlacentocac.) no dexar nada, o comprar todo quanto se vende. Alonso de Molina, Vocabulario en lengua castellana y mexicana y mexicana y castellana, 1571, part 2, Nahuatl to Spanish, f. 18r. col. 2. Thanks to Joe Campbell for providing the transcription.
Frances Karttunen:
CENTOCA to omit nothing, to continue something, to pursue something / no dejar nada, o comprar todo cuando se vende (M), lo continÚa, permanece (Z) [(2)Zp.97,194]. The Z sense of this follows from the literal senses of CEM ‘entirely’ and TOCA ‘to follow something.’ This contrasts with CENTŌCA ‘to plant things together.’ See CEM, TOCA. Frances Karttunen, An Analytical Dictionary of Nahuatl (Norman: University of Oklahoma Press, 1992), 31.