Christmas disease
Hemophilia (or haemophilia) B, a blood-clotting disorder in which a mutation of the Factor IX gene leads to a deficiency of Factor IX (or Christmas factor), a serine protease of the coagulation system. Both the factor and the disease are named for Stephen Christmas (not the holiday), the first patient discovered to have the condition in 1952. We haven't let our daughter participate in any more physical sports since she was diagnosed with Christmas disease last year.
Christmas graduate
A college or university student who discontinues his or her education after the end of the first term (i.e., around Christmastime). Primarily heard in US, South Africa. While I firmly believe in the importance of continued education, there are always a few Christmas graduates each year for whom college is just not well suited.
Christmas tree bill
In the US Congress, a minor bill that attracts many additional (and often unrelated) amendments attached to it, thus likened to ornaments hung upon a Christmas tree. Primarily heard in US, South Africa. If one really wants to see how corporate interests pervade the political process, one must simply examine the numerous amendments of the so-called Christmas tree bills that crop up each year.
cancel someone's Christmas
Sl. to kill someone; to destroy someone. (Underworld or jocular; the idea is that the dead person will not live until Christmas.) If he keeps bugging me, I'm gonna cancel his Christmas. Willie threatened to cancel Richard's Christmas if Richard didn't pay up.
Christmas comes but once a year.
Prov. Since Christmas only happens once a year, we should treat it as a special time by being good to others or by indulging children. Christmas comes but once a year, so we urge you to give to those less fortunate through this Christmas charity campaign.