obsession

noun

Etymology: From Latin obsessio (“a besieging”), from obsidere (“to besiege”); see obsess. Equivalent to obsess + -ion.

1. The quality of being obsessed; an unshakeable feeling that one topic or activity must be pursued above other interests.

   “My obsession with rugby resulted in me spending years following the sport.”

2. An idea that engenders a compulsive or irrational preoccupation, or the preoccupation thereby engendered.

   “The downfall of the chairman is an obsession that consumes Laura's time.”

3. An activity or entity that inspires a compulsive and potentially unhealthy fixation, or the fixation thereby inspired.

   “Editing Wikipedia started as a hobby, but it's turned into a complete obsession of mine.”

   “His current obsession is getting that law passed.”

4. Influence or control by evil spirits without possession.

   “if an evil spirit counterfeits the presence of God, and comes upon the man as an influence only, it may be described as obsession; but when a footing is gained in him, it is "possession," because the obsessing spirits have gained access, and possess the ground they hold, up to the extent of the ground given.”

   “They should see that a perception of their identification with the Victor of Calvary is absolutely necessary if they are to constantly and victoriously resist the obsession of evil spirits.”