n. [ L. obsessio: cf. F. obsession. ] 1. The act of besieging. [ archaic ] Johnson. [ 1913 Webster ]
2. The state of being besieged; -- used specifically of a person beset by a spirit from without. [ archaic ] Tylor. [ 1913 Webster ]
Whether by obsession or possession, I will not determine. Burton. [ 1913 Webster ]
3. An excessive preoccupation of the thoughts or feelings; the persistent haunting or domination of the mind by a particular desire, idea, or image. [ PJC ]
4. Hence: Any driving motive; a compelling goal; -- not necessarily implying a negative judgment, as does sense 3; as, the coach was obsessed with winning the state championship [ PJC ]
5. Something that causes an obsession{ 3 }. [ PJC ]
6. The state of being obsessed. [ PJC ]