drom-
course, racecourse, running, speed:
course, racecourse, running, speed:
dromond, dromedaries
drom-
combining form 
or dromo-
Etymology: Greek, from dromos 
1. : course : racecourse : running 
< Dromornis >
2. : speed 
< dromometer >
or dromo-
1.
< Dromornis >
2.
< dromometer >