to give pleasure to another person, help that person have fun (see Molina)
IPAspelling:
semeːltiɑ
Alonso de Molina:
cemeltia. nite. (pret. onitecemelti.) recrear y dar plazer a otro. Alonso de Molina, Vocabulario en lengua castellana y mexicana y mexicana y castellana, 1571, part 2, Nahuatl to Spanish, f. 16r. col. 1. Thanks to Joe Campbell for providing the transcription.