Origin: Latin suffix -ive
Obsessive has 4 different meanings across 2 categories:
a person who has obsessions
"The obsessive fan memorized every lyric and analyzed each frame of the music video for hidden clues about the artist's life."
A person who is obsessed, who has an obsession.
"The obsessive fan waited outside the stadium for hours just to get a glimpse of her favorite player."
characterized by or constituting an obsession
"the obsessional character of his response"
"obsessive gambling"
Prone to cause obsession.
"The detective's relentless pursuit of every minor detail became so obsessive that it drove his entire team to quit."
The word comes from the verb obsess, which originally meant to possess or hold someone's mind, combined with the suffix -ive. It describes something that possesses or holds one's attention persistently.