Easily excited; set off by the slightest excuse; easily enraged or inflamed.
Incapable of burning; not easily set on fire.
Capable of burning; easily set on fire.
Any inflammable substance.
Subject to changing and unpredictable emotional states; moody, capricious.
Of, related to, or caused by temperament.
User-unfriendly, unstable, that is complicated or has poorly written instructions and is subsequently difficult to operate.