[tuetuopay]

neither. even a shortcut saying like "total energy delivered" is not accurate, because it depends on how it is delivered and how it dissipates.

styropyro made a fascinating (if terrifying) video about it

[HPsquared]

Sounds a bit like fuse wire (except the frequency dependence)... There's both a current and a time component. High overloads can be tolerated for a very short time without blowing the fuse, while low overloads can be sustained for longer before the fuse reaches its maximum temperature and breaks.