Take leave of someone, as in We saw our guests off at the door, or They came to the airport to see us off. This expression was first recorded in 1809. Also see see out, def. 1.
The American Heritage® Idioms Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.