[unit] A gradus (plural: gradūs) is an ancient Roman unit of length that is 2.5 pedes. One gradus is 0.81 yards or 0.74 meters. There are 2 gradūs in one passus. kl`;m ``m, < j ...
• (n.) A dictionary of prosody, designed as an aid in writing Greek or Latin poetry.
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 ...
A - marching pace. B - military rank.
The marching step for a soldier. Also a military rank. 
Gra'dus noun [ From Latin gradus ad Parnassum a step to Parnassus.] A dictionary of prosody, designed as an aid in writing Greek or Latin poetry. « He set to work . . . without gradus or other help.» T. Hughes.