1. Only partly baked.
2. Informal. Insufficiently thought out; ill-conceived: a half-baked scheme.
3. Informal. Exhibiting a lack of good judgment or common sense: a half-baked visionary.

The American Heritage® Dictionary of the English Language, Fourth Edition Copyright © 2007, 2000 by Houghton Mifflin Company. Updated in 2009. Published by Houghton Mifflin Company. All rights reserved.