complimentary

Etymology

compliment + -ary

adj

1. In the nature of a compliment.
   a complimentary remark
   But yesterday evening late, when Lewis arrived from down town he found his supper spread, and some presents of books there, with very complimentary writings on the fly-leaves, and certain very complimentary letters, and more or less greenbacks of dignified denomination pinned to those letters and fly-leaves... August 25 1877, Mark Twain, The Letters of Mark Twain, volume 3,2004, page 56
2. Free; provided at no charge.
   complimentary drinks
   In the evenings, Ward and PJ offer guests a complimentary drink. This gesture seems to reinforce the hosts' desire to make everyone feel welcome. 2005, Vivien Lougheed, Belize Pocket Adventures, page 65
3. With respect to the closing of a letter, formal and professional.
   The complimentary closing is the word grouping used to bring the message or text to a close. 2003, Richard H. Beatty, The Perfect Cover Letter