1.  flashpoint(n = noun.state) flash point - point at which something is ready to blow up;
is a kind of criticality

2.  flashpoint(n = noun.attribute) flash point - the lowest temperature at which the vapor of a combustible liquid can be ignited in air;
is a kind of temperature

flashpoint, n.
1 the temperature at which vapour from oil etc. will ignite in air.
2 the point at which anger, indignation, etc. becomes uncontrollable.