If this is helpful - this is how our local recreational club describes its rides.

Easy: Under 10 mph
Leisurely: 10-12 mph
Steady: 12-14 mph
Moderate: 14-16 mph
Brisk: 16-18 mph
Strenuous: 18-21 mph
Super Strenuous: 22+ mph

Refers to the range of speeds on level ground without breaks. Downhills may be faster, uphills slower

Note: for rides described as HILLY, consider choosing a pace one step down from your usual comfort level