dont care
The central idea of a poem is the main theme that is represented in the poem. Topic is another word for theme.
main idea
Central theme or main concept.
motif, central idea, concept
sorrow.
grievous
If you mean "way OF sorrow," my first answer would be the "Via Dolorosa."
Any Human to Another is a poem written by Countee Cullen, a central figure in the Harlem Renaissance. It focuses on the universal nature of sorrow and suffering as a human experience shared by all.
The central idea of a writing is the theme.
lamentable, rue
sorrow,regret & dismay
the large sorrow