obsession

1 ENTRIES FOUND:
obsession /ɑbˈsɛʃən/ noun
plural obsessions
obsession
/ɑbˈsɛʃən/
noun
plural obsessions
Britannica Dictionary definition of OBSESSION
1 
: a state in which someone thinks about someone or something constantly or frequently especially in a way that is not normal
[count]
[noncount]
2 
[count]
a  : someone or something that a person thinks about constantly or frequently
b  : an activity that someone is very interested in or spends a lot of time doing

— obsessional

/ɑbˈsɛʃənl̟/ adjective [more obsessional; most obsessional]