MeaningTo be busy with something, or to work in a certain area.
HistoryThis word comes from the Bible. At first, it meant to be busy with something, sometimes in a way that caused an argument. Later, it came to mean being busy with any kind of work or study, which is what it means today.
Exampleהוא עוסק במכירת רהיטים ישנים.
He works in selling old furniture.