VAXen at home

That tends to be UK usage too. The thing under the bonnet (OK, hood) of a car is called an 'engine' over here. 'Motor' for that would be very uncommon. To me, a 'motor generator' is just that. An electric motor driving an electric generator, to be used to convert voltage/frequency, etc. A 'rotary converter' (or 'Dynamotor; if oyu go back far enough) is a simialr thing with common field windings/frame/etc rather than 2 separate electrical machines with the shafts coupled. A 'generator' over here is either just the mechanical-to-electircal energy converter or , as you said, a heat engine coupled to such a machine. Certainly if you hired a 'generator' (as somebody suggested we should do for a VCF-type event), you'd expect to get something with the engine included. I don't know how common these other term are across the Pond, but an 'alternator' is an AC-output geneterator, a 'Dynamo' (short for 'Dynamo-electric machine' is a generator, normally DC output, with a wound field, and a 'Magneto' (short for 'Magneto-electric machine' is a genatore with a permanent magnet field. Which means the common bicycle dynamo (as it's normally called over here' is in fact a magneto.... -tony