[riffraff]

What does "wasted" mean in this context?

[piva00]

It means that it doesn't generate any mechanical work, it's wasted as heat not captured for any other productive purpose (since waste heat can be useful in some contexts).

It's a measure of efficiency.

[weaksauce]

i assume heat since most energy in an ICE engine is wasted to heat (~60% wasted iirc)