In a 400-plus-word letter, Grant, who averages 19 points per game for the 8-4 Fighting Irish, said that he is no longer enrolled in school "due to an academic manner that [he] did not handle properly" and that, as a result, he is no longer a member of the basketball program.
Notre Dame coach Mike Brey said Grant's loss might be the biggest he's faced in his 14 seasons as the Irish head into ACC play for the first time.
"This one's going to be the hardest for two reasons: Jerian is so involved with everything we do on the offensive end of the floor, and we're trying to negotiate a new league," Brey said Monday.
Brey said he couldn't elaborate further because of privacy laws nor would he say when he found out Grant wouldn't be eligible for the spring semester.
Grant said that he intends to return to Notre Dame as soon as possible after the spring semester and will be patient with the process that he will eventually have to go through before being readmitted to the school.
"I think this is going to end in a great Notre Dame story," Brey said.
Brey said Grant would need to request a fifth year of eligibility from the school a year from now, after he completes his eighth semester in school.
The redshirt junior and son of former NBA player Harvey Grant had been on track to graduate in May 2014 with a degree in sociology.
Grant added that he takes responsibility for his "lack of good judgment and the poor decision," saying that he has no one to blame but himself.
Notre Dame students took their final exams this past week.
The situation appears to be similar to the one that the Notre Dame football program dealt with this past spring, when starting quarterback Everett Golson was also suspended from school for what he said were academic reasons that also surfaced right after final exam week.
Golson was just readmitted to Notre Dame on Dec. 13 after spending much of the fall season away from his Irish teammates and training in San Diego with quarterback trainer George Whitfield Jr. It is unclear how Grant will spend his time off.
Grant's fifth year at school next season would have been optional, with chances appearing strong that he would have left early for a shot at a professional-playing future after earning his degree. Now it appears that the 6-foot-5, 203-pounder will not have much of a decision to make at that time if he is still set on earning his degree from Notre Dame in the timeliest manner possible.
Brey isn't sure how the Irish will replace Grant, saying he and his staff must keep an open mind when the players return from break the day after Christmas. The Irish had been opening games with a small lineup but could start 6-foot-10 Tom Knight.
"We've got to look at a little bit of everything," Brey said.
The Associated Press contributed to this report.