Why do horses stand camped out? to “ sull, ” derived from the word sullen, means to refuse to advance. when encountering unfamiliar words like “ sull, ” it is essential to verify their validity and seek. 1992, cormac mccarthy, all the pretty horses: the mesteño pdf had stopped and sulled in the road with its forefeet spread and he sat looking after her. verb [ edit] sull ( lettera sull umanismo pdf third- person singular simple present sulls, present participle sulling, simple past and past participle sulled) ( intransitive) of an animal: to stop; to refuse to go umanismo on. skilled horsemanship is needed to return such a horse to a normal, responsive state. clear and concise communication lettera plays a vital role in effective exchange of ideas. a sulled- up horse is frozen in a tense mental state, often brought on by rough, forceful handling that creates fear and anxiety. spelling errors and misunderstandings can impede the flow of communication and create confusion. the importance of clarity in communication.