Engineers are those who meet the requirements of the Engineering Council, as incorporated or chartered Engineers.
Oh if only it were so, alas that isn't even the case in the UK which is the only place the EC holds any official sway. I say alas because like many professional engineers I would love it to be a protected professional designation, unfortunately this has yet to occur in the UK unlike some other parts of the world.
Whilst I am supportive of the EC, having received professional registrations through the IET where I remain an active volunteer, the EC's role in holding court over what does and does not constitute an engineer, and in the UK alone, is relatively neoteric. Engineers of course existed for some time prior to the 1981 creation of the EC, and should it one day cease to be, they shall of course continue to exist.
The 1982 Oxford Senior Dictionary I have just retrieved from above my desk defines:
An engineer as "a person who is skilled in a branch of engineering, one who is in charge of machines and engines, to construct or control as an engineer, to contrive or bring about.
Engineering is defined as: the application of scientific knowledge for the control and use of power.
More recent definitions decide an engineer to be someone who designs, builds, or maintains engines, machines, or structures or is a skilful contriver or originator of something.
The general summary I take from this however is original creation, perhaps original thought, using skill and a knowledge of scientific principles.
That is what I would personally consider to be an engineer, I know many engineers for whom I hold a great respect, but have never chosen to be professionally registered.
Any road up, although I do enjoy a healthy discourse and genuinely value this conversation (thank you), I fear we are rather spamming this thread about the chap's network cable with our exchange.