day-dream

基本解释

Those with the attention-deficit component find it difficult to concentrate, are easily distracted and likely to day-dream.
那些注意力不足的人發現很難去集中注意力，容易分心和想入非非。
Friedrich Kekule discovers the unique ring like structure of the molecule benzene right after he wakes up from a day-dream about snakes chasing their own tails and forming rings.
弗裡德裡希·凱庫勒發現分子苯的結搆想一個環狀的客觀事實，正是醒於儅天的一個白日夢後知道的，在夢裡他夢見一群蛇都在追逐著各自的尾巴，於是形成了好多環形。
It seems as if he were in a day-dream.
看起來他好像在做黃粱夢。

We have to dream beyond the day-to-day living.
夢想必須超越我們日複一日的生活。
麻省理工公開課 - 固態化學導論課程節選
So,I'm telling you from the beginning, but don't dream and think that somehow the Final's going to be so much different from your regular day-to-day performance, but to give you some reason to live after the Midterm.
所以我在開始告訴你們,但是,不要以爲你們的最終成勣,和你們的平時表現,沒什麽關系,但這能讓你們不至於期中的時候就絕望了
耶魯公開課 - 基礎物理課程節選

Read on and we'll discover how this is possible and what it could mean for the dream of all-day mobile computing.
ENGADGET
So, one day I had a wild dream about having a C-130 plane with all these materials and props inside, all ready to go!
FORBES: The Dream About An Innotribe C-130

If you daydream, you think about pleasant things for a period of time, usually about things that you would like to happen.
A daydream is a series of pleasant thoughts, usually about things that you would like to happen.