pureyoudaoicibaDictYouDict
pure: [13] Pure goes back ultimately to Latin pūrus ‘clean’, a word of ancient ancestry which was related to Sanskrit pūtás ‘purified’. It reached English via Old French pur. Amongst its Latin derivatives were the verbs pūrificāre ‘make pure’, source of English purify [14]; pūrāre ‘make pure’, which became French purer ‘purify, strain’, source of English purée [19]; and pūrigāre, later pūrgāre ‘purify’, source of English expurgate [17] and purge [14].
=> expurgate, purge
pure (adj.)youdaoicibaDictYouDict
c. 1300 (late 12c. as a surname, and Old English had purlamb "lamb without a blemish"), "unmixed," also "absolutely, entirely," from Old French pur "pure, simple, absolute, unalloyed," figuratively "simple, sheer, mere" (12c.), from Latin purus "clean, clear; unmixed; unadorned; chaste, undefiled," from PIE root *peue- "to purify, cleanse" (cognates: Latin putus "clear, pure;" Sanskrit pavate "purifies, cleanses," putah "pure;" Middle Irish ur "fresh, new;" Old High German fowen "to sift").

Replaced Old English hlutor. Meaning "free from moral corruption" is first recorded mid-14c. In reference to bloodlines, attested from late 15c.