American Heritage Dictionary
(2)
Century Dictionary
(2)
GNU Webster's 1913
(1)
WordNet
(1)
Elsewhere on the web
Res. 61, expressing the sense of the Congress that the United States flag flown over the United States Capitol should be lowered to half-mast one day each month in honor of the brave men and women from the United States who have lost their lives in military conflicts.— Daily Kos
I am also informed by the estimable Meteor Blades that "half-mast" is a naval term, and that on land (where the United States Capitol is currently located), the preferred terminology is "half-staff."— Daily Kos
Fox news has reported that in honor of the lives lost at Virginia Tech, President Bush has instructed the American People that flags are to be flown at half-mast until Sunday evening.— Red Hispanic - A Townhall.com user blog
David Foster Wallace All literary flags at half-mast, rightfully so.— Expecting Rain
German Chancellor Angela Merkel expressed her horror at what she called a "horrendous crime," while Interior Minister Wolfgang Schaeuble said flags would fly at half-mast across the country on Thursday.— The Border Mail

If you'd like to prod us on getting a pronunciation for this word, sign in (or sign up) and let us know.
Bubble size: how much this word was used in a year
Bubble height: used more or less than expected, vs. all uses evenly distributed
You can expect to see this word a few times a year.