The Latin word for sweetheart is puella. The word sweetheart in Spanish is novio, in Italian it is Tesoro, and in French it is amoureux.
amoureux
occupé
occupé(e)
"Sweetheart" is most often rendered as "Chérie" (fem.) and "chéri" (masc.) in French.
Cherie
The word 'sweetheart' in Indonesian is sayang.
busy is translated "occupé / occupée" in French.
Cheri/e
Mon chéri.
In Cajun French, you can say "cher(e)" or "mon cher" to mean sweetheart.
bien-aimé