In the company of; also, in addition to. For example, He arrived at the theater together with his girlfriend, or The lawyer found the will, together with other papers, in the murdered man's files. [Late 1400s] For a synonym, see along with.
The American Heritage® Idioms Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.