What does Mabel mean?
A medieval short form of Amabel, from Latin amabilis 'lovable, dear', from amare 'to love'. The long-surviving English form of the amabilis names.
What does Regina mean?
From the Latin 'regina', meaning 'queen' (feminine of 'rex'). Long used as a title of the Virgin Mary (Regina Caeli, 'Queen of Heaven'). A literal, well-established 'queen' name.