rather

• Not a quick pick me up--rather, a stubbornly slow one.
• The ichor actually has naught to do with a chorus, being rather the Greek word for the ethereal fluid that flowed in the veins of the Gods in place of blood; it has in English taken on more practical meanings to do with emanating fluids.
• He wrote in Latin rather than the Italian vernacular and, being a colorful person, he even wrote a few letters to Virgil and Cicero of Ancient Rome —  Conservapedia - Recent changes [en]
• It wasn't until 1857, when Matthew Arnold took on the position, that it started to resemble its modern form: Arnold was the first professor to deliver his lectures in English rather than Latin, and to speak about contemporary literature. —  Expecting Rain
• Not because using Linux is difficult -- rather, the task at hand with getting personnel and equipment up to the challenge is daunting. —  Intranet Journal

Roget's II: The New Thesaurus

Allen's Synonyms and Antonyms