Definitions
A reference book used as an aid in writing classical verse.
Word origin
From Gradus ad Parnassum (Latin, literally, a step to Parnassus), a 17th-century prosody dictionary long used in British schools. Doublet of grade.
Source: Wiktionary, CC BY-SA 4.0
Used as a crossword answer1 curated clues
01“Verse reference”6 letters
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