“ A poem in which the poet retracts a view or sentiment expressed in a former poem.
Origin --> Late 16th century: via Latin from Greek ‘palinōidia’, from palin 'again' + ōidē 'song'.
Academic Articles on the poem
Article 1 -- Gates
Article 2 - Perloff
Easter 1916 - Jackman
Easter 1916 - Dyson
Poetry Foundation - Mlinko
