Fetching details from the dictionary...
rumination; regurgitation; chewing the cud
turning over in one's mind; thinking over (something); pondering; musing; rumination (about a subject)
牛が草を反芻している姿が見られた。
Cattle could be seen ruminating on grass.
師の教えを何度も反芻して理解を深めた。
By repeatedly reflecting on the master's teachings, they deepened their understanding.
過去の失敗を反芻して同じ過ちを避けた。
By reflecting on past failures, they avoided repeating the same mistakes.