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Webster 1913 Edition
Monomania
Monˊo-ma′ni-a
,Noun.
[
Mono-
+ mania
.] Derangement of the mind in regard of a single subject only; also, such a concentration of interest upon one particular subject or train of ideas to show mental derangement.
Syn. – Insanity; madness; alienation; aberration; derangement; mania. See
Insanity
.