1. quantity：qty; 定额，数量
2. quantity：quant; 数量性
1. 数量;量
A quantity is an amount that you can measure or count.
e.g. ...a small quantity of water.
少量的水
e.g. ...vast quantities of food...
大量食品
2. 大量;大宗；大批
Things that are produced or available in quantity are produced or available in large amounts.
e.g. After some initial problems, acetone was successfully produced in quantity...
解决了最初的一些问题之后，终于成功地制造出了大量丙酮。
e.g. But even with those databases, the sheer quantity of data can still cause problems.
可是即便有了那些数据库，数据的数量之大仍然会带来问题。
3. (尤指和质量相对的)数量
You can use quantity to refer to the amount of something that there is, especially when you want to contrast it with its quality.
e.g. ...the less discerning drinker who prefers quantity to quality...
不求质、但求量的不那么识货的饮酒者
e.g. In terms of quantity, production grew faster than ever before.
从数量上看，产量增长的速度比以往任何时期都要快。
4. 未知量;未知数
If you say that someone or something is an unknown quantity, you mean that not much is known about what they are like or how they will behave.
quantity
e.g. He is an unknown quantity for his rivals.
对于对手们而言，他是个未知数。
词典解释
1. 数量;量
A quantity is an amount that you can measure or count.
e.g. ...a small quantity of water.
少量的水
e.g. ...vast quantities of food...
大量食品
2. 大量;大宗；大批
Things that are produced or available in quantity are produced or available in large amounts.
e.g. After some initial problems, acetone was successfully produced in quantity...
解决了最初的一些问题之后，终于成功地制造出了大量丙酮。
e.g. But even with those databases, the sheer quantity of data can still cause problems.
可是即便有了那些数据库，数据的数量之大仍然会带来问题。
3. (尤指和质量相对的)数量
You can use quantity to refer to the amount of something that there is, especially when you want to contrast it with its quality.
e.g. ...the less discerning drinker who prefers quantity to quality...
不求质、但求量的不那么识货的饮酒者
e.g. In terms of quantity, production grew faster than ever before.
从数量上看，产量增长的速度比以往任何时期都要快。
4. 未知量;未知数
If you say that someone or something is an unknown quantity, you mean that not much is known about what they are like or how they will behave.
quantity
e.g. He is an unknown quantity for his rivals.
对于对手们而言，他是个未知数。
quantity 情景对话
订货
B：Do you offer any quantity discounts ?
大量购买有折扣吗？
A：No, we don‘t.
不，没有。
B：Then give us three cases of this .
那么这种的就买三箱好了。