adj. Able to be ignored or excluded from consideration; too small or unimportant to be of concern.
the GNU version of the Collaborative International Dictionary of English
adj. That may be neglected, disregarded, or left out of consideration; too small or unimportant to be worthy of notice.
The Century Dictionary and Cyclopedia
Capable or admitting of being neglected or disregarded; neglectable.
WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
adj. so small as to be meaningless; insignificant
adj. not worth considering
Word Usage
"Officials tell us that the amount of anthrax found in the mail was what they call negligible, that it actualy required two tests to even find it, so they don't think it's a large amount."