rice shop; rice dealer
Refers to a store that sells rice, or a person/business dealing in rice. A straightforward, everyday noun.
I bought brown rice at the neighborhood rice shop.
祖父は若い頃、米屋を営んでいた。
My grandfather ran a rice dealership when he was young.
Compound of 米 (こめ, 'rice') and 屋 (や, 'shop' or 'dealer'). A straightforward occupational/store name.