SIGNIFICANT FIGURES (noun)

 

Digits in a measurement that indicate the precision of the measurement. These figures include all those that are known with certainty plus one more, which is an uncertain estimate.

Example: "0.4346" has four "sig figs;" with the "434" known and the "6" an estimate. The number "4.346 * 10^-1" also has four sig figs. The number "0.0078" has only two sig figs, whereas "0.007800" has four sig figs; these numbers could also be written as "7.8 * 10^-3" and "7.800 * 10^-3," respectively. "1.0078" has five sig figs, while "10.0078" has six sig figs.