It is a title of respect or courtesy, equivalent to the English Sir. It was used in the Ottoman Empire and Byzantine Empire. It follows the personal name, when it is used, and is generally given to members of the learned professions and to government officials who have high ranks, such as bey or pasha. It may also indicate a definite office, as hekim efendi, chief physician to the sultan. The possessive form efendim (my master) is used by servants, in formal discourse, when answering the telephone, and can substitute for "excuse me" in some situations (e.g. asking someone to repeat something).
In the Ottoman era, the most common title affixed to a personal name after that of agha was efendi. Such a title would have indicated an "educated gentleman", hence by implication a graduate of a secular state school (rü?diye), even though at least some if not most of these efendis had once been religious students, or even religious teachers.[not verified in body]
Lucy Mary Jane Garnett wrote in the 1904 work Turkish Life in Town and Country that Ottoman Christians, women, mullahs, sheiks, and princes of the Ottoman royal family could become effendi, a title carrying "the same significance as the French Monsieur" and which was one of two "merely conventional designations as indefinite as our "Esquire" has come to be.[in the United Kingdom]".
The Republican Turkish authorities abolished the title circa the 1930s.
Effendi is still used as an honorific in Egypt, Jordan, and Turkey (as well as some other former Ottoman states), and is the source of the word afandim?, Turkish: efendim, a particularly polite way of saying, "Excuse me?", and can be used in answering the phone.
The colonial forces of British East Africa and German East Africa were built from a stock of Sudanese soldiers of the Egyptian army, which was nominally under the Ottoman Empire. These units entered East Africa with some officers who brought their title of effendi with them and, thus, it continued to be used for non-European officers of the two colonial forces. Up to the present the Swahili form afande is a way to address officers in the armies of Kenya, Tanzania and recently in Rwanda with the coming to power of RPF.
Effendi was also a non-European's officer rank in the Schutztruppe of German East Africa. Similar to the above British practice, Effendis were promoted by a governor's warrant, not by a kaiser's commission, as white commissioned officers were. Effendis had no authority over white troops. In the Schutztruppe this rank was used, together with other ranks of Ottoman origin like "Tschausch" (sergeant) and "Ombascha" (corporal).