No, it appears to be related to Spanish or Italian. The spanish word for happy is Alegre).
Allegra = simkha (שמחה)
Allegra Leguizamo's birth name is Allegra Sky Leguizamo.
Allegra Cohen's birth name is Allegra Larayne Cohen.
Allegra Riggio's birth name is Allegra Louise Riggio.
Allegra De Vita's birth name is Allegra Ann De Vita.
Allegra Cottone's birth name is Allegra Lucia Cottone.
Allegra Kent's birth name is Cohen, Iris Margo.
No
Allegra is Italian-derived and means: jaunty and joyful.
Yes. Of course it is!
Allegra and Allegra D were invented in the Nineties. It is a beautiful Italian name that has been around since the days of the Romans. It means happy and jaunty. Tell people, "What? That stuff? Why my name comes from the days of the early Italians and it means heappy and jaunty. They gave that drug my name because of it's meaning."
Allegra