Meaning & use
significant figure
Last updated
Meaning
nouncountable
A digit in a number that shows how precise the measurement is, including all nonzero digits and some zeros.
Grammar: Countable noun; often used in the plural: significant figures.
Patterns
- to three significant figures
- significant figures in a number
The answer should be rounded to three significant figures.
In the number 0.00456, there are three significant figures: 4, 5, and 6.
Word forms
| plural | significant figures |
|---|
Common combinations
- to X significant figures
- Express the result to two significant figures.
- count significant figures
- When counting significant figures, leading zeros do not count.
- round to significant figures
- Round 1234 to three significant figures to get 1230.
Synonyms and how they differ
- sig fig
- Informal abbreviation used in science and engineering; significant figure is the full term.
Word family
- significance noun
- The quality of being important or meaningful; in statistics, the likelihood that a result is not due to chance.
- significant adjective
- Important or notable; in measurements, indicating precision.
Commonly confused: significant figure or decimal place?
significant figure vs decimal place
Decimal places count digits after the decimal point; significant figures count all digits that carry meaning, including before the decimal point.
Practice
How many significant figures are in the number 0.00720?
Choose one answer.
The leading zeros (0.00) are not significant. The digits 7, 2, and the final 0 are significant, giving three significant figures. Option A would ignore the trailing zero, which is significant because it comes after a decimal point and a nonzero digit.
Make it your own
Write a sentence using “significant figure”, then check it and compare it with the examples above.