The phrase “posthumous” is pronounced as “PAH-st(h)yuh-muhs”. It’s an adjective which means “occurring, revealed, or produced after the dying of the particular person to whom it’s attributed”.
The phrase is commonly used to explain artistic endeavors, literature, or music which are launched after the artist’s dying. For instance, the novel “The Silmarillion” by J.R.R. Tolkien was revealed posthumously in 1977, 4 years after his dying.
