Clerihew is a whimsical, skewed quatrain poem–– two rhyming couplets (aabb) of unequal length about a person’s biography. 

From A Poet’s Glossary

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

The British detective writer Edmund Clerihew Bentley (1875-1976) invented this form of comic poetry. It consists of a skewed quatrain –– two rhyming couplets (aabb) of unequal length that whimsically encapsulate a person’s biography. The form spoofs metrical smoothness. There is usually something ludicrous in the dead-pan send-up of a famous person, whose name appears as one of the rhymed words in the first couplet:

Geoffrey Chaucer 
Could hardly have been coarser, 
But this never harmed the sales 
Of his Canterbury Tales.

Bentley prefaced his three volumes of capsule biographies, collected in Clerihews Complete (1951), with these “Introductory Remarks”:

The Art of Biography 
Is different from Geography.
Geography is about Maps, 
But Biography is about Chaps. 

G. K. Chesterton (1874 – 1936) and W. H. Auden (1907- 1973) were both devotees of the clerihew.

See also Limerick.

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