(Italian) and (Spanish) form of Theresa. In the English-speaking world the name is often chosen in this spelling by Roman Catholics, with particular reference to the Spanish saint, Teresa of Ávila (Teresa Cepeda de Ahumada, 1515–82).
Scottish, English, and Irish: 1. from the Middle English, Old French personal name Michel, vernacular form of Michael. 2. nickname for a big man, from Middle English michel, mechel, muchel ‘big’. 3. Irish (County Connacht): surname adopted as equivalent of Mulvihill.