regrettable

Etymology

regret + -able

adj

1. Able to be regretted, especially deserving of regret.
   The officers' actions were regrettable, yes, but there's nothing to be done now but to relocate everyone to the mainland in a calm and orderly manner.
   Jeeves: Foreign travel often liberates emotions best kept in check, sir. The air of North America is notoriously stimulating in this regard, as witness the regrettable behavior of its inhabitants in 1776. B. Wooster: Hm? What happened in 1776, Jeeves? Jeeves: I prefer not to dwell on it, if it's convenient to you, sir. May 12 1991, “Kidnapped!”, in Jeeves and Wooster, Series 2, Episode 5