showing a negligible or permissible deviation from a standard an accurate ruler
without error; precise; meticulous
(to n significant digits) representing the first n digits of the given number starting with the first nonzero digit, but approximating to the nearest digit in the final position since π = 3.14159…, the approximation 3.1416 is accurate to 5 significant digits.
(to n decimal places) giving the first n digits after the decimal point without further approximation π = 3.1415 is in this sense accurate to 4 decimal places
accurately, adverb accurateness, noun
C16: from Latin accūrātus, past participle of accūrāre to perform with care, from cūra care
1610s, "done with care," from L. accuratus "prepared with care, exact," pp. of accurare "take care of," from ad- "to" + curare "take care of" (see cure). The notion of doing something carefully led to that of being exact (1650s). Related: Accuracy.