an arm that is overworked (throws too much); or, to have a strong arm, throwing things a lot (see Molina)
IPAspelling:
mɑːtɬɑhpɑltik
Alonso de Molina:
matlapaltic. ni. ser bracero, tirando mucho. Alonso de Molina, Vocabulario en lengua castellana y mexicana y mexicana y castellana, 1571, part 2, Nahuatl to Spanish, f. 53r. col. 2. Thanks to Joe Campbell for providing the transcription.
Frances Karttunen:
MĀTLAHPALTIC someone very strong / bracero que tira mucho (M), es en gran manera fuerte (C) [(1)Cf. 110V]. See MĀ(I)-TL, TLAHPALTIC. Frances Karttunen, An Analytical Dictionary of Nahuatl (Norman: University of Oklahoma Press, 1992), 139.