A mania restricted to one thing or idea.

synonym: possession.

Roget 503: disordered reason, disordered intellect; diseased mind, unsound mind, abnormal mind; derangement, unsoundness; psychosis; neurosis; cognitive disorder; affective disorder^†.    insanity, lunacy; madness etc. adj.; mania, rabies, furor, mental alienation, aberration; paranoia, schizophrenia; dementation^†, dementia, demency^†; phrenitis^†, phrensy^†, frenzy, raving, incoherence, wandering, delirium, calenture of the brain^†; delusion, hallucination; lycanthropy^†; brain storm^†.    vertigo, dizziness, swimming; sunstroke, coup de soleil [Fr.], siriasis^†.    fanaticism, infatuation, craze; oddity, eccentricity, twist, monomania (caprice) 608; kleptodipsomania^†; hypochondriasis [Med.] etc. (low spirits) 837; melancholia, depression, clinical depression, severe depression; hysteria; amentia^†.    screw loose, tile loose, slate loose; bee in one's bonnet, rats in the upper story.    dotage etc. (imbecility) 499.    ... show more

Roget 606: obstinateness etc. adj.; obstinacy, tenacity; cussedness [U.S.]; perseverance etc. 604.1; immovability; old school; inflexibility etc. (hardness) 323; obduracy, obduration^†; dogged resolution; resolution etc. 604; ruling passion; blind side.    self-will, contumacy, perversity; pervicacy^†, pervicacity^†; indocility^†.    bigotry, intolerance, dogmatism; opiniatry^†, opiniativeness; fixed idea etc. (prejudgment) 481; fanaticism, zealotry, infatuation, monomania; opinionatedness opinionativeness^†.    mule; opinionist^†, opinionatist^†, opiniator^†, opinator^†; stickler, dogmatist; bigot; zealot, enthusiast, fanatic.    ... show more

Dutch: monomanie
Polish: monomania