Webster's New World College Dictionary Copyright © 2010 by Wiley Publishing, Inc., Cleveland, Ohio.
Informal thus (sense )
Used by arrangement with John Wiley & Sons, Inc.
The American Heritage® Dictionary of the English Language, 4th edition Copyright © 2010 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
adverb Usage Problem
Thus.Usage Note: Thusly was introduced in the 19th century as an alternative to thus in sentences such as Hold it thus or He put it thus. It appears to have first been used by humorists, who may have been echoing the speech of poorly educated people straining to sound stylish. The word has subsequently gained some currency in educated usage, but it is still often regarded as incorrect. A large majority of the Usage Panel found it unacceptable in an earlier survey. In formal writing thus can still be used as in the examples above; in other styles this way, like this, and other such expressions are more natural.