Principal English Translation: 

at the royal palace of (a necessarily possessed form; see attestations and see Karttunen)

Frances Karttunen: 

-CHĀN, a necessarily possessed form, at the home of / en casa del (C) This must be possessed; unlike a postposition, it cannot bind with another noun to the exclusion of a possessive prefix. Z gives ĪCHĀMPA with the stative gloss ‘his vicinity,’ but the suffixed –PA should convey a directional sense. When the honorific -TZIN is bound to –CHĀN, then locative –C(O) is suffixed to the whole construction, ĪCHĀNTZINCO ‘at his home (H).’ See CHĀN-TLI.
Frances Karttunen, An Analytical Dictionary of Nahuatl (Norman: University of Oklahoma Press, 1992), 45.

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