(每日一词）grain

Grain  /ɡreɪn/ n. （尤指像稻谷、小麦等像草一样的植物的）谷粒，颖果，谷（物）

meaning: a seed or seed from a plant, especially a plant like a grass such as rice or wheat 

联想：g-谷物 + rain 雨水

e.g. Grain is one of the main exports of the American Midwest. 谷物是美国中西部地区主要的出口商品。