an estuary of the sea (see Molina); literally, an arm or branch of a body of water
IPAspelling:
ɑːmɑːitɬ
Alonso de Molina:
amaitl. estero de mar. Alonso de Molina, Vocabulario en lengua castellana y mexicana y mexicana y castellana, 1571, part 2, Nahuatl to Spanish, f. 4r. col. 2. Thanks to Joe Campbell for providing the transcription.