ONS is an abbreviation for "Over Night Studying", SON can also be used in some occasions. It is an action held by most, if not all, petroleum engineering students. It has been well known through out time, that this habit is to be practiced before major exams, and even quizes. According to new Petroleum engineering students, ONS is a sacred retual, that every -successful to be- engineer should experience!
"Normal student Helal" : Ughh, Got a midterm tomorrow, ONS :D ??
2 years later..
"ADMA executive manager HaLool :3" : SON was worth it alright :3!