The terminology is new to fans and players alike. And judging by all the noise coming from Hawaii, it is not very popular.
If you happened to come across the designation "MDF" well down the list of names through 36 holes of the Sony Open over the weekend, don't feel bad for not knowing what it meant.
Many of the PGA Tour players affected didn't, either.
The letters stand for "made [cut] didn't finish" and it altered the weekend plans of 18 players in the Sony field who were given credit for making the 36-hole cut, received FedEx Cup points and were paid.
But just like someone who did not make the cut, those 18 players did not get to finish the tournament.
They were the victims of a new PGA Tour rule in 2008 designed to keep field sizes manageable.
"I think it stinks," Jim Furyk told reporters. "I'm not a big fan of it and I don't understand why we're doing it and I much like a hard number. The reason I say that is I think one week you could finish tied for 63rd and you could be playing the next week [and] you could finish tied for 63rd and you can't, you're not going to be playing. You don't have an opportunity. And I just couldn't disagree with that more."
Regular PGA Tour events, which typically start with fields of 132, 144 or 156 players, have long had a 36-hole cut with the top 70 players and ties advancing to the final two rounds.
But in November, in an effort to keep field sizes smaller, the PGA Tour Policy Board enacted a new rule: The top 70 and ties still make the cut. But if the cut exceeds 78 players, only the number nearest to 70 continues in the tournament.
In the case of the Sony, there were 87 players who finished at even-par 140 or better. The nearest number to 70 was 69 players at 1-under 139 or better. So 18 players were credited with a made cut and paid $9,699.
Of course, unlike others who made the cut, they did not have the opportunity to improve their position or perhaps even play to win the tournament. The fact that several players over the years have made the cut on the number and gone on to win is cause for some concern. So is the fact that many didn't know about the new rule -- although they have only themselves to blame for that.
"I don't understand the rule," John Daly told the Golf Channel after making the cut on the number but being unable to continue. "I think it's crazy. It's a stupid rule, I'm sorry. I grinded my butt off to shoot even. Then I find out on 18 you might not be playing. I just wish we would have known."
The Players Advisory Council recommended the change because of several instances in which tournament fields swelled into the 80s. By paring down the field, it improves the pace of play and makes pairings more manageable in the event of poor weather or the need for two-tee starts dictated by daylight or television concerns.
But it is confusing for players battling to make the cut. Some weeks, they might actually have to go one lower to assure themselves of the chance to keep playing.
According to the PGA Tour, the cut has included more than 78 players 136 times over the past 12 years, or about 11 times a year. There were 508 players who would have been affected by this new rule had it been in force during that time, but just one went on to a top-5 finish: Anthony Kim, who shot 69-64 at the Zurich Classic last year to move up from a tie for 64th.
Some have suggested making cuts the top 65 and ties or -- in the case of a tournament that exceeds 78 players -- let them all play on Saturday and have another cut to 60 and ties for Sunday.
But no rule change can be implemented until 2009, which leaves a simple solution for this year. Play better.
Bob Harig is a frequent contributor to ESPN.com. He can be reached at BobHarig@gmail.com.