c.1300, "knowledge (of something) acquired by study," also "a particular branch of knowledge,"
from O.Fr. science, from L. scientia "knowledge,"
from sciens (gen. scientis), prp. of scire "to know,"
probably originally "to separate one thing from another, to distinguish,"
related to scindere "to cut, divide,"
from PIE base *skei- (cf. Gk. skhizein "to split, rend, cleave," Goth. skaidan, O.E. sceadan "to divide, separate;" see shed (v.)).

Modern sense of "non-arts studies" is attested from 1670s.
The distinction is commonly understood as between theoretical truth (Gk. episteme) and methods for effecting practical results (tekhne), but science sometimes is used for practical applications and art for applications of skill.

Main modern (restricted) sense of "body of regular or methodical observations or propositions ... concerning any subject or speculation" is attested from 1725; in 17c.-18c. this concept commonly was called philosophy.
To blind (someone) with science "confuse by the use of big words or complex explanations" is attested from 1937, originally noted as a phrase from Australia and New Zealand.