Polite noun for the time of a meal, often used in everyday conversation.
ご飯時になったら、みんな食堂に集まります。
When it's mealtime, everyone gathers in the dining hall.
ご飯時は家族で食卓を囲むのが習慣です。
It's our custom to sit around the table as a family at mealtime.
Compound of ご飯 (polite form of 飯, 'meal') and 時 (とき, 'time'), with rendaku voicing of とき to どき.