A somewhat emphatic or old-fashioned way to say 'cooked rice', often used in proverbs or to contrast with other foods.
Cooked rice and miso soup are the basics of the Japanese table.
something one never tires of
Idiomatic use, often in the phrase 「米の飯と女は飽きぬ」 (one never tires of rice and women). Rare in modern conversation.
There is an old saying: 'One never tires of rice and women.'