|—n , pl -duses|
|1.||a book of études or other musical exercises arranged in order of increasing difficulty|
|2.||prosody a dictionary or textbook of prosody for use in writing Latin or Greek verse|
|[C18: shortened from Latin Gradus ad Parnassum a step towards Parnassus, a dictionary of prosody used in the 18th and 19th centuries]|
a dictionary of Greek or Latin prosody and poetic phrases used as an aid in the writing of verse in Greek or Latin. The term is derived from the Gradus ad Parnassum ("A Step to Parnassus"), a 17th-century prosody dictionary long used in British schools.
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