Blazon is a poetic form that catalogs a beloved’s physical features or attributes.

From A Poet’s Glossary

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

Blazon, or blason, is a French heraldic term meaning “coat of arms.” In literature, a blazon is a catalog of the beloved’s physical features or attributes. 

The convention goes back to the thirteenth century. The blazon, a male form, relies on a series of comparisons, usually drawn from nature, that tend to come from a stock of images in the Song of Songs. Petrarch made the blazon a prominent part of his Rime Sparse (1374) and it thus became central to the Petrarchan tradition. Elizabethan lyricists are especially known for detailing the physical beauty of their mistresses. [Edmund] Spenser provides a well-known example in the tenth stanza of Epithalamium (1595):

Her goodly eyes like sapphires shining bright, 
Her forehead ivory white, 
Her cheeks like apples which the sun hath rudded, 
Her lips like cherries charming men to bite, 
Her breasts like to a bowl of cream uncrudded,
Her paps like lilies budded,
Her snowy neck like to a marble tower, 
And all her body like a palace fair. 

Ernst Robert Curtius uses the term recipes for medieval codes proscribing head-to-toe body descriptions. Mikhail Bakhtin speaks of the “dual fact, complete ambivalence, and contradictory fullness” of the blazon. Clément Marot launched a literary fashion with his erotic “Blazon du Beau Tétin” (“Blazon of the Beautiful Beast,” 1536), which inaugurated the vogue for “anatomical blazons” (blasons anatomiques), descriptive poems in praise of the parts of the female body. John Davies of Hereford’s poem “Some blaze the precious beauties of their loves” critiques those who write blazons for their hyperbolic comparisons (“Yet I by none of these will blazon mine”), and then proceeds to praise his beloved with a sense of wordless wonder (Wit’s Pilgrimage, 1605). The convention inevitably became clichéd and thus led to parody, or the contreblazon (anti-blazon). Robert Greene mocks the traditional blazon in Menaphon (1589):

Thy teeth like to the tusks of fattest swine, 
Thy speech is like the thunder in the air:
Would God thy toes, thy lips, and all were mine. 

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