Early 19th century; earliest use found in Lord Byron (1788–1824), poet. From Italian Mamma mia, lit. ‘mother mine!’ from mamma mother + mia, feminine of mio my.
Definition of Mamma mia in US English:
Mamma mia
exclamationˌmamə ˈmiːə
Expressing surprise, astonishment, or approval.
Origin
Early 19th century; earliest use found in Lord Byron (1788–1824), poet. From Italian Mamma mia, lit. ‘mother mine!’ from mamma mother + mia, feminine of mio my.