the GNU version of the Collaborative International Dictionary of English
adj. Capable of being assailed.
The Century Dictionary and Cyclopedia
Capable of being assailed, attacked, or invaded.
WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
adj. not defended or capable of being defended
Word Usage
"Scientific reasoning is assailable, that is what peer review is for and is exactly how and why the amazing errors in the IPCC report were found out and shot down."