True. So I decided to do a search just using heat as term, and lo and behold Wkipedia article starts off with essentially verbatim of paddoboy's cut&paste piece. So yes I stand corrected in respect of standard terminology. One wonders how to understand then the logic of 'heat transfer' as not inherently redundant, as also 'heat exchanger' or more tellingly 'heat content'. Still, I now realize it always pays to do a web search rather than relying on a dimly recalled school education when as here definitions can be all-important.