monomania

UK: /ˌmɒnəʊˈmeɪnɪə/

US: /ˌmɑnəˈmeɪniə, -ˈmeɪnjə/

US: (mon′ə mā′nē ə, -mān′yə)

WordReference Random House Learner's Dictionary of American English © 2026

mon•o•ma•ni•a /ˌmɑnəˈmeɪniə, -ˈmeɪnyə/   n. [uncountable]

1. an overwhelming interest or zeal in a single thing:
   The captain's monomania was authority.

mon•o•ma•ni•ac /ˌmɑnəˈmeɪniˌæk/  n. [countable]

WordReference Random House Unabridged Dictionary of American English © 2026

mon•o•ma•ni•a  (mon′ə mā′nē ə, -mān′yə), n. 

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.

• Neo-Latin; see mono-, -mania
• 1815–25;

mon•o•ma•ni•ac  (mon′ə mā′nē ak′), n.  mon•o•ma•ni•a•cal  (mon′ə mə nī′ə kəl), adj. 

Collins Concise English Dictionary © HarperCollins Publishers::

monomania / ˌmɒnəʊˈmeɪnɪə/ noun

1. an excessive mental preoccupation with one thing, idea, etc

ˌmonoˈmaniˌac noun , adjective

monomaniacal / ˌmɒnəʊməˈnaɪək^əl/ adjective