from The American Heritage® Dictionary of the English Language, 4th Edition
- adj. Not defined clearly or distinctly: an ill-defined concept; an ill-defined view across the foggy moor.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- adj. Poorly defined; blurry, out of focus; lacking a clear boundary.
from The Century Dictionary and Cyclopedia
- Not distinct; not well marked out: as, an ill-defined sensation; specifically, in zoology, without definite borders: said of marks, depressions, etc.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- adj. poorly stated or described
ill + defined (Wiktionary)