Refers to the time for a meal; somewhat old-fashioned or literary. In modern casual speech, 食事時 (しょくじどき) is more common.
Since it was mealtime, I headed to the dining hall.
Compound of 時分 (jibun, 'time') + 時 (toki/doki, 'time'). The exact historical derivation is uncertain, but it literally means 'time-time'.