monomania [mon-uh-mey-nee-uh, -meyn-yuh]
1. (no longer in technical use) a psychosis characterized by thoughts confined to one idea or group of ideas.
2. an inordinate or obsessive zeal for or interest in a single thing, idea, subject, or the like.
Origin: 1815-25; < New Latin; see mono-, -mania
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