Meaning

adverb on the contrary

adverb to some (great or small) extent

adverb more readily or willingly

originFrom Middle English rather, from Old English hraþor, comparative of hraþe (“soon, early, fast”). More at rathe. Cognate with Dutch radder (“faster”), comparative of Dutch rad (“fast; quick”), German Low German radd, ratt (“rashly; quickly; hastily”), German gerade (“even; straight; direct”). By surface analysis, rathe + -er.

Etymology from Wiktionary, CC BY-SA 3.0