As I understand it "warm" was proposed just to provide a transitive
verb to replace "[the temperature of the system] rises", or (less
obviously) "[the internal energy of the system] increases".
What I don't understand is why such a verb is needed in the physical
vocabulary. "Heat" is a perfectly good transitive verb. In physical
vocabulary it applies to situations where the temperature of the
system remains unchanged (e.g. the melting of a cake of ice). It is
also the case that a system can be "warmed" by working on it.
My point is this: We already have all the words we need to describe
the processes about which physics can usefully say something. Would
it not complicate matters to introduce terms gratuitously? Is rigor
so distasteful that we must introduce poetry to sweeten it?