double-precision
Technical term in computing and numerical analysis, referring to floating-point numbers with twice the precision of single-precision. Used as both a noun and adjectival noun.
This calculation requires the use of double-precision floating-point numbers.
Performing operations in double precision reduces errors.
浮動小数点数 (floating-point number) is the general term; 倍精度 specifies the precision level.
Compound of 倍 (double) and 精度 (precision), a direct calque of English 'double-precision'.