- 1[uncountable] the state in which a person's mind is completely filled with thoughts of one particular thing or person, in a way that is not normal Her fear of flying is bordering on obsession. obsession with somebody/something The media's obsession with the young prince continues.
- 2[countable] obsession (with somebody) a person or thing that someone thinks about too much Fitness has become an obsession with him.
Check pronunciation: obsession