Likely a variant of Joyce, a French-derived name from a Breton personal name later associated with joy.
Joise is likely a variant of Joyce, a French-derived name from a Breton personal name later associated with joy. That history gives the name a pleasant double life: one rooted in older Celtic and French transmission, and another in the modern feeling of happiness suggested by its later sound association.
Joise keeps that brightness while changing the shape. The name feels understated and lightly unusual. It has enough familiarity to seem approachable, but the spelling gives it a faintly tailored quality. Joise belongs to the family of names that have been softened or revised over time, and it carries the kind of gentle elegance that comes from long linguistic travel.