coachfellow means one of a pair of horses employed to draw a coach. Lexicurio rates it Sui generis — a strength score of 89 out of 100.
Etymology
From coach + fellow.
noun
- One of a pair of horses employed to draw a coach.
- A comrade.“[…] I have grated upon my good friends for three reprieves for you and your coach-fellow Nym […]”