Is there such a word as "cowing," as in "The Quarter horse is good at cowing."?

My friend is selling her quarter horses, and we were working up the ad. She wanted me to put that sentence in, that said they were good at “cowing,” but I said, “There is no such word!”

She insisted that there is. She started to explain what it meant, and I interrupted and said, “I know what you mean by it, but there is no such word!”

She’s a little miffed and she is never wrong!

Of course, I can’t find it, only variations of:
“To cow,
verb (used with object)

1.to frighten with threats, violence, etc.; intimidate; overawe.”

Cower, etc.