Rather is defined as preferably or more accurately.(adverb)
An example of rather used as an adverb is wanting to live on the west coast rather than on the east coast.
See rather in Webster's New World College Dictionary
Origin: ME < OE hrathor, compar. of hrathe, hræthe, quickly: see rathe
See rather in American Heritage Dictionary 4
Origin: Middle English
Origin: , from Old English hrathor
Origin: , comparative of hrǽthe, quickly, soon
Origin: , from hrǽth, quick. Usage Note: In expressions of preference rather is commonly preceded by would: We would rather rent the house than buy it outright. In formal style, should is sometimes used: I should rather my daughter attended a public school. Sometimes had appears in these constructions, although this use of had seems to be growing less frequent: I had rather work with William than work for him. This usage was once widely criticized as a mistake, the result of a misanalysis of the contraction in sentences such as I'd rather stay. But it is in fact a survival of the subjunctive form had that appears in constructions like had better and had best, as in We had better leave now. This use of had goes back to Middle English and is perfectly acceptable. • Before an unmodified noun only rather a is used: It was rather a disaster. When the noun is preceded by an adjective, however, both rather a and a rather are found: It was rather a boring party. It was a rather boring party. When a rather is used in this construction, rather qualifies only the adjective, whereas with rather a it qualifies either the adjective or the entire noun phrase. Thus a rather long ordeal can mean only “an ordeal that is rather long,” whereas rather a long ordeal can also mean roughly “a long process that is something of an ordeal.” Rather a is the only possible choice when the adjective itself does not permit modification: The horse was rather a long shot (not The horse was a rather long shot). See Usage Notes at have, should.
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