In response to a threatened Arab boycott, the World Bank and International Monetary Fund have advanced the date of the 1982 annual meeting in Toronto by almost a month to avoid a conflict with the major Muslim festival of Idd Ul-Adha.

The re-scheduling of the meeting, recently approved by the executive boards, but not publicly announced, is the second such accommodation to the influential Arab group, although complaints by Israel over repeated conflicts with the Jewish holidays of Rosh Hashanah and Yom Kippur have been turned aside. For example, at the 1981 annual meeting in Washington, the first two days of a four day session coincided with the Jewish New Year.

In 1975, at the request of the Arab nations, the annual meeting was put forward to the end of August, instead of the traditional end-of-September period, to avoid a conflict with the holy month of Ramadam.

At the annual meeting this year, a group of Arab nations formally petitioned the IMF and Bank to change the dates of the 1982 meeting from Sept. 28 through Oct. l to avoid the conflict with Idd Ul-Adha, a feast marking the end of the annual pilgrimage to Mecca, and said to be one of the two most important Islamic holidays.

Adding to the Arab sense of urgency was the fact that a member of their group, a Kuwaiti, was scheduled to be chairman of the joint session for the first time. But Canadian officials, to whom the Arabs also appealed separately, originally said that all available hotel space for the large group was unavailable in Toronto at any other time.

But after long negotiations, the IMF and Bank were able to book space for the joint conference from September 6 through 9 at the Sheraton Centre, but not for key preliminary meetings running from September 1 through 5. These will take place at a nearby Holiday Inn. Canadian Government officials said yesterday in response to a query that the later dates were "open," but that the Canadian Bar Association had booked the Centre for the prior week.

Bank and IMF officials say they try hard to avoid conflicts with all religious holidays, but that their fluctuating dates on the calendar, coupled with the difficulty of pinning down hotel space for a session now attended by more than 10,000 persons, makes some conflicts inevitable.

Last year, when Israeli officials complained about the then prospective dates of this year's meeting, IMF-Bank officials responded they had not known of the conflict with the New Year, and that time was too short, in any event, to make a change. The Israeli delegation was present in Washington, but did not attend during their New Year holiday. The governor of the Israeli central bank then sent officials a 10-year calendar showing future dates of the Jewish religious holidays.