the arms of a cross, or the wooden cross piece of a cross (see Molina)
(contains a loanword from Spanish: cruz, cross)
Alonso de Molina:
ixtlapal yatica cruz. los brazos dela cruz, o el madero atrauesado dela cruz. Alonso de Molina, Vocabulario en lengua castellana y mexicana y mexicana y castellana, 1571, part 2, Nahuatl to Spanish, f. 48r. col. 1. Thanks to Joe Campbell for providing the transcription.