opera seria
Concise Oxford English Dictionary © 2008 Oxford University Press:
opera seria /ˈsɪərɪə/
▶noun (pl. opere serie /ˌɒpere ˈsɪərɪe/) an opera, especially one of the 18th century in Italian, on a serious theme.
– origin Ital., lit. ‘serious opera’.
'opera seria' also found in these Oxford entries:

