grain

corn, crop, grain

这些名词都有“谷物”之意。
corn: 主要指大麦、小麦、燕麦、裸麦、玉蜀黍这5种谷物及其粒子。
crop: 指谷物或果类等一年或一季的收成，也可指地里的农业作物或谷物。
grain: 指稻、麦等谷类及其粒子。

molecule, atom, particle, speck, grain

这些名词均有“粒、微粒”之意。
molecule: 指物质中保持原物质的一切化学性质，能独立存在的最小微粒，即分子。
atom: 指元素的最小粒子，其体积比molecule小。
particle: 指任何物质的微粒，引申指任何小的部分。
speck: 一般指“微点”或“微粒”，可引申指“斑点、污点”。
grain: 通常指能为肉眼清楚看到的颗粒，比上述几个词所表“粒”的体积大。

名词 grain:

1. a small hard particle
2. foodstuff prepared from the starchy grains of cereal grasses
   同义词：food grain, cereal
3. a weight unit used for pearls or diamonds: 50 mg or 1/4 carat
   同义词：metric grain
4. 1/60 dram; equals an avoirdupois grain or 64.799 milligrams
5. 1/7000 pound; equals a troy grain or 64.799 milligrams
6. dry seedlike fruit produced by the cereal grasses: e.g. wheat, barley, Indian corn
   同义词：caryopsis
7. the direction or texture of fibers found in wood or leather or stone or in a woven fabric

动词 grain:

1. thoroughly work in
   同义词：ingrain
2. paint (a surface) to make it look like stone or wood
3. form into grains
   同义词：granulate
4. become granular
   同义词：granulate

1. We ship grain to Africa.
   我们把谷物运往非洲。
2. Their speculative buying of grain is illegal.
   他们投机购买谷物是不合法的。
3. Stores of grain are frequently attacked by pests.
   储存的谷物经常受到害虫的破坏。
4. He used a miller to mill the grain into flour.
   他用碾磨机把谷物磨成面粉。
5. A single grain of a cereal plant.
   谷粒禾谷类作物的一个颗粒
6. Grain is their chief export.
   谷物是他们的主要出口物资。

grain

n.Abbr. gr.（名词）缩写 gr.

A small, dry, one-seeded fruit of a cereal grass, having the fruit and the seed walls united.Also called caryopsis
谷粒：谷草的小且干燥的单种子果实，果实与种壁连在一起也作 caryopsis
The fruits of cereal grasses especially after having been harvested, considered as a group.
谷物：谷草果实的总称，尤指已收割后的
Cereal grasses considered as a group:
谷草的总称：
例句：
a field of grain.
种植谷物的田地

A relatively small discrete particulate or crystalline mass:
颗粒，细粒：相对微小的，分离的颗粒或晶体物质：
例句：
a grain of sand.
一粒沙子

A small amount or the smallest amount possible:
微量：一点儿，少许或最小的可能的量：
例句：
hasn`t a grain of sense.
没有一点意义

Aerospace A mass of solid propellant.
【太空学】 块状燃料：一块固体推进剂
A unit of weight in the U.S. Customary System, an avoirdupois unit equal to 0.002285 ounce (0.0'5 gram).See table at measurement
格令：美国惯用体系的重量单位，一常衡单位等于0.002285盎斯（0.0'5克）参见 measurement
The arrangement, direction, or pattern of the fibrous tissue in wood.
纹理：木头的纤维组织的排列、方向或图案

The side of a hide or piece of leather from which the hair or fur has been removed.
粗糙面：皮革的除去毛发的一面
The pattern or markings on this side of leather.
带这种面式样或标记的皮革
The pattern produced, as in stone, by the arrangement of particulate constituents.
纹理：由微小成份的排列所产生的图案，如石头中的
The relative size of the particles composing a substance or pattern:
微粒的大小：构成物质或图案的微粒的相对尺寸：
例句：
a coarse grain.
粗糙的微粒

A painted, stamped, or printed design that imitates the pattern found in wood, leather, or stone.
纹理图案：模拟木头，皮革或石头的纹理所画出的，压模的或印刷出来的图案
The direction or texture of fibers in a woven fabric.
织理：纺织品中线的走向或组织
A state of fine crystallization.
完美结晶的状态

Basic temperament or nature; disposition.
气质，性情：基本的脾性或天性；气质
An essential quality or characteristic.
本质：本质或本质特征
Archaic Color; tint.
【古语】 染料；颜色
v.（动词）
grained,grain.ing,grains
v.tr.（及物动词）
To cause to form into grains; granulate.
使…成粒状：使…成为颗粒；使…成为粒状
To paint, stamp, or print with a design imitating the grain of wood, leather, or stone.
漆成木纹状：绘画，压模或印刷一个图案来模拟石头，皮革或石头的纹理
To give a granular or rough texture to.
给…以粒状或粗糙的结构
To remove the hair or fur from (hides) in preparation for tanning.
去掉（皮的）毛发以准备鞣制
v.intr.（不及物动词）
To form grains.
形成颗粒

<习惯用语>with a grain of salt
With reservations; skeptically:
半信半疑地：有保留地；怀疑地：
例句：
Take that advice with a grain of salt.
半信半疑地接受建议

来源：
Middle English
中古英语
from Old French graine
源自 古法语 graine
from Latin gr3num * see g—…-no-
源自 拉丁语 gr3num *参见 g—…-no-

【引伸】
grain.er
n.（名词）