magnum opus

US /ˌmæɡ.nəm ˈoʊ.pəs/
UK /ˌmæɡ.nəm ˈoʊ.pəs/
"magnum opus" picture
1.

obra maestra, magnum opus

a large and important work of art, music, or literature, especially one regarded as the most important work of an artist or writer.

:
His latest novel is considered his magnum opus.
Su última novela es considerada su obra maestra.
The symphony is widely regarded as the composer's magnum opus.
La sinfonía es ampliamente considerada la obra maestra del compositor.