award, reward, prize三者的含义基本相同，但在不同语境中表达的含义有所差别

award 

1.指正式地或官方地颁发，授予，给予；

2.也可以指法庭裁决给予。【它指一种官方的奖励行为，往往鼓励在工作中达到成就或所提出的要求而进行一种奖励。强调荣誉而不在乎奖品的大小或奖金的多少。award的“奖品”是因优点奖励或授予的东西，】如：
The school principal awarded a prize in history to the best student.学校校长将历史奖授予最出色的学生。

3.award 还可指XX奖
比如“金球奖”就是“Golden Globe Award”，不能说“Golden Globe Prize”

reward

“报答，报偿，奖赏”，多指对某人的工作或服务等的报答。如：
The fireman received a reward for saving the child's life.
因救了小孩的命，消防员提到一笔奖金。

prize 

“奖赏，奖金，奖品”，多指在各类竞赛、竞争或抽彩中所赢得的奖。【这种奖赏有的凭能力获得，有的凭运气获得。】如：
Hundreds of prizes can be won in our newspaper competition.
参加我们报纸的竞赛可以赢得数以百计的奖品。

如：the Nobel prize 诺贝尔奖。

award (give after careful consideration, esp. officially)经仔细考虑后正式的“给予，授予（奖品等）”；作名词时表示“奖品，奖金”。

A medal was awarded to him for his good conduct. 他因品行优良被授予奖章。

He was awarded first prize. 他获得了一等奖。

They awarded scholarship to the best students. 他们把奖学金授予最好的学生。

reward(give as a return for sth. done)因做某事给予“回报，酬劳，奖赏”；作名词表示“报酬，奖励，报答”。

They rewarded her for her help. 他们答谢他的帮助。

Anyone who finds it will be rewarded. 凡找到它的人都将获得酬谢。

He was given $800 as a reward for his bravery. 他因表现勇敢而得到800美元的赏金。

注意：在结构上，award后可接双宾语；award sb. sth(通常为奖金或奖状)。reward后只接一个宾语，通常以人或人的行为为宾语，句型是reward sb. with sth.。

They awarded her the Nobel Prize. 他们授予他诺贝尔奖。

He rewarded her with money for her heroic deeds. 他为她的英雄行为而给她奖金。

Her efforts were rewarded with success in career. 她的努力使她获得了事业的成功。

prize 作名词“奖品，奖金”Offered or given as a prize:作为奖品提供或给予的：

作动词“珍视，珍藏；估价，评价”

We prize honor above money.

我们珍视荣誉甚于金钱。

The boy's robot toy was his most prized possession.

那男孩的玩具机器人是他最珍惜的东西。

作形容词“得奖的，作为奖品的”

a prize novel得奖小说a prize cup.奖杯

短语：

be awarded a prize for 因……而获奖

win /carry off a prize获奖

award，reward
这两个词都可以用作名词和动词，作名词时，意义相近，但不是同义词。
作名词时，award的意思是“奖品”、“奖金”，其义与prize近似，两者都指因为作出杰出成就而受奖。例：
The Olympic winner received a gold medal as an award．
He won the second award of $ 2，000．
而reward作名词时，其意为“赏金”、“酬金”或一些非金钱的报酬。例：
We will offer a reward of ten thousand dollars for information about the case．
如果有人提供有关案件的情报，我们愿意出一万元赏金。
We don't expect substantial rewards．我们并不期望得到优厚的报酬。
用作动词时，award的意思是“授与”、“颁发”、“判给”；reward则表示“报答”、“酬谢”之意。例：
He was awarded the first prize for Outstanding Industrial Design．他获杰出工业设计一等奖。
We judge awarded him twenty thousand dollars as damages．法官判给他二万元作为赔偿费。
You should reward them according to their deserts．你应该对他们论功行赏。
Is that how you reward me for my help？你就是这样来报答我给你的帮助吗？
reward也可以用于比喻意。例：
I would feel amply rewarded if my book—A Study of English Twins—could be of some help to the readers．