Naked poetry is a term for free-verse poetry written without a set form and stripped of any artifice or ornament. 

From A Poet’s Glossary

The following definition of the term naked poetry is reprinted from A Poet's Glossary by Edward Hirsch.

Naked poetry is a term for the radical modern impulse to strip poetry down to its bare essentials. Lafcadio Hearn coined the phrase naked poetry for one of his general lectures at the Imperial University in Tokyo (1896–1903). He said:

I want to make a little discourse about what we might call Naked Poetry . . . that is, poetry without any dress, without any ornament, the very essence or body of poetry unveiled by artifice of any kind.

The sparseness and classical restraint of Japanese poetry helped lead Hearn to the concept. The Spanish poet Juan Ramón Jiménez also invented the termpoesia desnuda (naked poetry) in Eternidades (1916–1917). In his poem “At first she came to me pure” he remembers how poetry first came to him in his youth as a naked young girl “dressed only in her innocence,” and he loved her. Gradually she dressed up and put on more ornaments and he started to hate her without knowing why.  Years later she sheds her clothes and returns as a young girl again: “Naked poetry, always mine, / that I have loved my whole life!”

The impulse to a pure and exposed poetry has had many modern articulations. Charles Baudelaire took the title My Heart Laid Bare (1887) for his intimate journals, which were never completed, from Edgar Allan Poe, who said that if any man dared to write such a book with complete frankness it would be a masterpiece. “But to write it — there is the rub,” Poe said: “No man dare write it. No man ever will dare write it.  No man could write it, even if he dared. The paper would shrivel and blaze at every touch of the fiery pen” (1848).

W. B. Yeats’s 1914 poem “A Coat” personifies his “song” as a coat embroidered with old mythologies, which he then sheds: “For there’s more enterprise / In walking naked.” In 1921, the Yiddish poet Peretz Ravitch published a collection entitled Nakete Lider (Naked Songs). The Greek poet Pantelis Prevalakis borrowed Jiménez’s phrase and called his second and third books The Naked Poetry (1939) and The Most Naked Poetry (1941). He wanted a verse free of artifice, sincere and unguarded, bare. Jiménez’s naked poetry, which was translated by Robert Bly, had a strong influence on American poets of the 1960s and ’70s. In 1969, Stephen Berg and Robert Mezey borrowed Jiménez’s phrase for their anthology, Naked Poetry, which they followed seven years later with The New Naked Poetry. These anthologies of free-verse poetry in open forms reflect their conviction that “the strongest and most alive poetry in America has abandoned or at least broken the grip of traditional meters and had set out, once again, into ‘the wilderness of unopened life.’” They suggest that poems “take shape from the shapes of their emotions.”

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