elegant variation
Definition - The unnecessary use of synonyms to avoid using the same word twice in a sentence or a passage.

Example -
To be or not to exist, that is the question.

Etymology -
The term was coined by H. W. Fowler so that he could condemn the practice. When he coined the term in the 1920s, elegant had the (since lost) pejorative connotation of "precious over-refinement."

Oxford English Dictionary -
The term's first citation is from 1906:
"The locking of arms is … only an elegant variation for clinging."
(H. W. & F. G. Fowler King's English iii. 178)

Quotation -
"It is the second-rate writers, those intent rather on expressing themselves prettily than on conveying their meaning clearly, & still more those whose notions of style are based on a few misleading rules of thumb, that are chiefly open to the allurements of elegant variation. … The fatal influence … is the advice given to young writers never to use the same word twice in a sentence — or within 20 lines or other limit."
(Source: Fowler's Modern English Usage)

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