decimal fraction
B2Formal, Technical, Academic
Definition
Meaning
A number less than 1 represented using a decimal point and digits to its right, showing tenths, hundredths, etc.
Any fractional number expressed in the base-10 positional notation system, including numbers greater than 1 that have a fractional part. Also refers to the system of notation itself.
Linguistics
Semantic Notes
Often used interchangeably with 'decimal' in mathematics. Emphasizes the fractional part of a number. Can be distinguished from a 'vulgar fraction' (e.g., 1/2).
Dialectal Variation
British vs American Usage
Differences
No significant differences in meaning. UK English may slightly favour 'decimal' alone in general contexts, while 'decimal fraction' remains standard in technical writing in both regions.
Connotations
Neutral and technical in both varieties.
Frequency
Low frequency in everyday speech; higher frequency in educational, scientific, and financial contexts. Frequency is comparable in UK and US English.
Vocabulary
Collocations
Grammar
Valency Patterns
The [number/result] is a decimal fraction.Convert the [vulgar fraction/percentage] into a decimal fraction.Express the value as a decimal fraction to [number] places.Vocabulary
Synonyms
Strong
Neutral
Weak
Vocabulary
Antonyms
Phrases
Idioms & Phrases
- “[None directly associated]”
Usage
Context Usage
Business
Used in financial reporting, accounting, and precise measurement (e.g., 'The interest rate is expressed as a decimal fraction: 0.05').
Academic
Core concept in mathematics education and scientific notation (e.g., 'The result was a repeating decimal fraction').
Everyday
Rare in casual conversation; might appear when discussing measurements, money, or DIY (e.g., 'You need 0.75 litres – that's a decimal fraction').
Technical
Precise term in mathematics, engineering, and computer science for non-integer numeric representation.
Examples
By Part of Speech
verb
British English
- The programme will decimalise the fraction.
- We need to decimalise these values for the calculation.
American English
- The program will decimalize the fraction.
- We need to decimalize these values for the calculation.
adverb
British English
- [Not commonly derived]
American English
- [Not commonly derived]
adjective
British English
- Use decimal fraction notation.
- The decimal fraction system is base-ten.
American English
- Use decimal fraction notation.
- The decimal fraction system is base-ten.
Examples
By CEFR Level
- 0.5 is a decimal fraction.
- One half is the same as the decimal fraction 0.5.
- To calculate the discount, convert 15% to the decimal fraction 0.15.
- A recurring decimal fraction like 0.333... goes on forever.
- The survey results were presented as decimal fractions to two decimal places for greater precision.
- You can approximate the vulgar fraction 1/7 as the decimal fraction 0.142857.
- The algorithm's precision depends on its ability to handle infinite decimal fractions without significant rounding errors.
- In financial modelling, converting ratios into weighted decimal fractions is a standard preprocessing step.
Learning
Memory Aids
Mnemonic
Think of DECIMAL FRACTION as a FRACTION that uses the DECIMAL system (based on 10) with a dot.
Conceptual Metaphor
A PART of a WHOLE, sliced into powers of ten.
Watch out
Common Pitfalls
Translation Traps (for Russian speakers)
- Do not translate as 'децимальная дробь' (obsolete/historical). The correct equivalent is 'десятичная дробь'.
- Avoid confusing with 'decimal point' (десятичная запятая/точка).
Common Mistakes
- Writing '0,5' (using a comma) in English texts – the correct form is '0.5'.
- Incorrectly calling the whole number part the 'decimal fraction'.
- Pronouncing '0.25' as 'zero point twenty-five' instead of 'zero point two five' or 'nought point two five' (UK).
Practice
Quiz
Which of the following is NOT a decimal fraction?
FAQ
Frequently Asked Questions
In strict terms, a 'decimal fraction' refers specifically to the fractional part less than 1 (e.g., .75 in 3.75). In common usage, especially in education, 'decimal' is often used as a shorthand for the same concept, and 'decimal fraction' can also refer to any number expressed in decimal notation, including the whole number part.
Yes, it is a terminating decimal fraction representing one quarter. The '0' before the point indicates the whole number part is zero.
They provide a standardised, base-10 system for writing fractions, which simplifies arithmetic operations like addition, subtraction, and comparison compared to using vulgar fractions (e.g., 1/3 + 1/4). They are essential for most scientific, financial, and digital calculations.
A decimal fraction where one or more digits repeat infinitely. For example, 1/3 = 0.333..., where the digit '3' recurs. It is often denoted with a dot over the repeating digit(s) (0.3̇).