Word · Frequency #23934
downcasts
向下转换；向下转型
downcasts is the plural of downcast.
In computing, a cast that converts a value from a supertype to a subtype; a downcast.
编程术语
- 1.
An act of looking downwards, usually as a sign of discouragement, sadness, etc., or sometimes modesty; hence (uncountable, archaic), dejection, melancholy.
向下看的动作,通常表示沮丧、悲伤,有时表示谦逊；引申为沮丧、忧郁
- 2.
a ventilation shaft through which air enters a mine
进风井
- 3.
A cast (“change of expression of a data type”) from supertype to subtype.
(数据类型)从父类型到子类型的转换
- 4.
A ventilating shaft down which air passes in circulating through a mine.
矿井中空气下行通风的通风井
进风井；通风井；低头；沮丧；忧郁；向下看的动作,通常表示沮丧、悲伤,有时表示谦逊；引申为沮丧、忧郁；进风井；(数据类型)从父类型到子类型的转换
In use
The miners entered the mine through the downcast to access the lower levels.
Fresh air flows down the downcast, providing ventilation to the underground tunnels.
The engineer inspected the downcast for any blockages that could reduce airflow.
Connections
Collocations
- downcast shaft
- 进风井；下行通风井
- Fresh air travels down the downcast shaft into the mine.新鲜空气沿着进风井下行进入矿井。
- downcast of the eyes
- 低垂的目光
- The downcast of her eyes revealed her modesty.她低垂的目光流露出她的谦逊。
- explicit downcast
- 显式向下转换
- The compiler rejected the code because it required an explicit downcast.编译器拒绝了这段代码，因为它需要显式向下转换。
Synonyms
- dejection
- 沮丧；失意；情绪低落 · 较正式，指因挫折或失败而缺少精神与希望；比 downcast 作名词表示此义时常用，但仍属书面语。
- melancholy
- 忧郁；愁思；持久的哀伤 · 语域偏文学，强调较深且持续一段时间的心境，不只是瞬间的低落。
Learner notes
Memory Tip
把“cast”（投射）想象成目光向下投：眼睛朝下看，自然显得沮丧或谦卑——记住“down（向下）+ cast（投射）”就是垂头丧气的样子。
Context & Register
语域：mixed 常见场景：文学/正式写作、采矿工程、编程/软件开发 含义因语境而异：采矿工程中指“进风井”，编程中指“从父类型到子类型的向下转换”；而“低头/沮丧”的用法比较正式，多用于文学或书面语。
Grammar Note
该词作为可数名词，指矿井中的进风井。
Pronunciation & Spelling
All six words rhyme with the target's final syllable in American English: each ends in /ˌkæst/ (cast itself /kæst/). Watch out for the lookalike 'castle' /ˈkæsəl/, which is spelled with 'cast' but has a silent 't' and a different vowel; and be aware that in British English, the '-cast' ending is often pronounced /kɑːst/ rather than /kæst/.
Learn the forms together
页面下方列出了常见词形变化。学习时注意它们在句子中的语法位置。
Dictionary facts from ECDICT, WIKTIONARY.