const
const — noun
1. a written abbreviation for 'constant', used in computing to label a value or var
a written abbreviation for 'constant', used in computing to label a value or variable that the programmer does not intend to change while a program runs.
Haruto declared a const variable for the sales tax rate in the code.
const + variable/noun for a fixed value in code
Using const helps other programmers see which values should stay the same.
The team lead asked Wei to mark all unchanging settings with const.
A bug appeared because someone changed a const value during the loop.
- variable
a value that can change; var or let in many languages
用法筆記
In many programming languages such as C++, JavaScript, and Rust, 'const' is a keyword written in lowercase. It is typically placed before a variable declaration to signal that the variable's value cannot be reassigned after initial assignment.
常見錯誤
2. a written abbreviation for 'constitution' or 'constitutional', used in legal wri
a written abbreviation for 'constitution' or 'constitutional', used in legal writing and official documents to refer to a country or state's founding legal document.
The judge referred to Article V of the U.S. Const. during the hearing.
Const. with period + Article [number] + of
Gabriela found the relevant clause in the state const. after searching for an hour.
The professor asked the class to read the Const. of Japan before the next seminar.
A change to the const. requires approval from two-thirds of the legislature.
用法筆記
When written with an initial capital letter and a period (Const.), it almost always refers to a specific constitution. Used informally within legal case citations and academic footnotes.
3. a written abbreviation for 'construction', used in project plans, signs, and eng
a written abbreviation for 'construction', used in project plans, signs, and engineering documents to refer to the process of building or assembling something.
The const. of the new hospital wing is scheduled to finish in March.
const. of + [building/infrastructure project]
Ravindra checked the const. schedule before ordering the steel beams.
A bright orange sign near the site read 'Under Const. — Stay Clear.'
Delays in const. pushed the opening of the bridge back by six weeks.
用法筆記
Common on roadside signs ('Under Const.'), in architectural blueprints, and in civil engineering reports. The full form 'construction' is more common in everyday writing.
4. a written abbreviation for 'constant', used in mathematics and science to refer
a written abbreviation for 'constant', used in mathematics and science to refer to a quantity or number that remains the same across all situations or calculations.
The speed of light is a well-known const. in physics equations.
const. as a label for a mathematical/scientific invariant
Aylin wrote the value of const. π on the board for the geometry class.
Students often forget that this const. appears twice in the same formula.
The research paper listed each const. in a table before the experiment began.
- invariant
more formal; used in advanced mathematics and computer science
- variable
a quantity that can change in an equation or experiment
用法筆記
Used in textbooks, scientific papers, and mathematical proofs to save space. Unlike the programming sense (const keyword), this sense always refers to the underlying invariant value itself, not to a language keyword.