Tra từ cram - Từ điển Oxford Advanced Learner 8th

cram [cram crams crammed cramming] BrE [kræm] NAmE [kræm] verb (-mm-)
1. transitive, intransitive to push or force sb/sth into a small space; to move into a small space with the result that it is full
•~ sb/sth into/onto sth He crammed eight people into his car.
•~ sth in I could never cram in all that she does in a day.
•~ sth + adv./prep. I managed to cram down a few mouthfuls of food.
•~ sth Supporters crammed the streets.
•~ sth full I bought a large basket and crammed it full of presents.
•~ into/onto sth We all managed to cram into his car.
2. intransitive ~ (for sth) (NAmE, informal or rather old-fashioned, BrE)to learn a lot of things in a short time, in preparation for an exam
Syn: ↑swot
•He's been cramming for his exams all week.
Verb forms:

Word Origin:
Old English crammian, of Germanic origin; related to Dutch krammen ‘to cramp or clamp’.