RasulAllah sallAllahu alayhi wa sallam being an "ummi" the least offensive translation is untaught, even one of the meanings has negative connotations. but untaught is the closest to our aqidah. untutored is another fair translation. al-iyadhubillah - illiterate means incapable of reading. "not being taught" and "incapable" are like the sky and the earth. unlearned means "did not learn" and this has connotations of the state being perpetual. in other words, this word appears as: "did not learn and stayed that way". uneducated is deeper in its implication. educated is not just learning to read, but also implies good manners, cultured and so forth. uneducated is a connotation for being uncultured and ill-mannered in addition to not being capable of reading. unread is lighter, but still undesirable. but indicates lack of knowledge. a scientist can be unread in theology. while the person is himself learned, he lacks knowledge in a particular field because he has not learned it, he has not read about it. unschooled is also similar because it only indicates absence of formal study under a teacher or in a school format. but unfortunately, it is commonly used as a synonym for illiterate. and hence undesirable. unlettered is also used as a synonym for illiterate or ignorant or someone who does not know how to read or write WITH the implication that such a person is not knowledgeable. uninstructed is not bad. but also has connotations of "remaining thus thereafter" --- i propose a new word "adidact". [if it has been used, i am not aware]. auto-didact is someone who is self-taught. this comes from greek: === we will use the prefix a- to negate that one was taught, as is done with words of greek origin: so the word would now be: adidact: a person who was not taught by anyone [a-didadct]. deididact: a person who was taught ONLY by God. Allah ta'ala knows best.