from The American Heritage® Dictionary of the English Language, 4th Edition
- n. A mild state of mania, especially as a phase of a manic-depressive cycle.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. A mild form of mania, especially the phase of several mood disorders characterized by euphoria or hyperactivity.
from The Century Dictionary and Cyclopedia
- n. A mildly maniacal state of short duration.
From hypo- + mania, after German Hypomanie. (Wiktionary)