In the previous Halacha we have discussed in general the law that one must wait six hours after eating meat before eating dairy foods either because the nature of meat is to get stuck between one’s teeth or because meat gives off a taste in one’s mouth for a prolonged amount of time.
The Rambam (end of Chapter 9 of Hilchot Ma’achalot Assurot) writes: “If one eats meat, whether the meat of an animal or of poultry, he may not eat dairy foods afterwards until he waits the amount of time which is ‘between one meal and the next,’ which is approximately six hours.” The Kol Bo and Orchot Chaim write likewise.
We must take notice though that the Rambam does not write that one must wait six hours; rather, he writes “approximately six hours”. It is well-known that the Rishonim, especially the Rambam, used extremely precise language when writing. Does this specific designation of “approximately six hours” have any halachic ramification?
Maran Rabbeinu Ovadia Yosef zt”l writes lengthily to prove from the words “approximately six hours” that there is no need to wait six complete hours and it is sufficient if five-and-a-half hours have elapsed and it is close to the six-hour mark (for in the Talmud, “close” refers to within a half-hour’s time). This can likewise be inferred from the words of the Meiri who writes, “six hours or close to it.”
However, the Sefer Ginat Veradim writes that one must wait six complete hours and other Poskim rule likewise, based on sources from the Talmud and Poskim.
Maran zt”l therefore concludes by ruling that one should preferably not eat dairy products until six complete hours have passed, even if one has only eaten poultry. However, if one acts leniently and eats dairy foods after five-and-a-half hours have elapsed when there is a need to do so, one has on whom to rely, especially if one has only eaten poultry, in which case there is even more room for leniency.
The reason why there is more room for leniency with regards to poultry is because eating poultry with milk is not forbidden by Torah law and is merely a rabbinic injunction. Thus, the prohibition of eating dairy foods after eating poultry is not on the same level as the prohibition as eating dairy after having eaten meat.
Summary: Preferably, one should always wait six hours between eating meat and dairy. One who acts leniently and waits only five-and-a-half hours in a case of great need has on whom to rely, especially after eating only poultry.