brittle
     adj 1: having little elasticity; hence easily cracked or fractured
            or snapped; "brittle bones"; "glass is brittle";
            "`brickle' and `brickly' are dialectal" [syn: {brickle},
             {brickly}]
     2: lacking warmth and generosity of spirit; "a brittle and
        calculating woman"
     3: (of metal or glass) not annealed and consequently easily
        cracked or fractured [syn: {unannealed}]
     n : caramelized sugar cooled in thin sheets [syn: {toffee}, {toffy}]
Source: WordNet® 2.0

brittle adj. Said of software that is functional but easily broken by
   changes in operating environment or configuration, or by any minor tweak
   to the software itself. Also, any system that responds inappropriately
   and disastrously to abnormal but expected external stimuli; e.g., a file
   system that is usually totally scrambled by a power failure is said to
   be brittle. This term is often used to describe the results of a
   research effort that were never intended to be robust, but it can be
   applied to commercial software, which (due to closed-source development)
   displays the quality far more often than it ought to. Oppose {robust}.


Source: The Jargon File