Crossword

[Big Bas]

Scottish dialect word to describe uncooperative restless horses

Probably    r?e?a

[Quizmonster]

'Reesty' is an answer which fits the description perfectly. Sadly, it's not very close to fitting the pattern you offer!
The appropriate verb, meaning  for a horse to be uncooperative, is 'reest'. Might your final 'a' be wrong?