[grey-duh
s] 
| a work consisting wholly or in part of exercises of increasing difficulty. |
[grey-duhs] | a dictionary of prosody, esp. one that gives word quantities and poetic phrases and that is intended to aid students in the writing of Latin and Greek verse. |
gradus
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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