I went to a career fair once where a company was hiring ROR devs. They gave out guitar picks and drumsticks and everything.

I disagree. I don't find many similarities between what I do and what a "real engineer" does. I do not consider myself an engineer; I write software. Nowhere in the 18 years I've been doing this for money have I met anybody that could explain what software engineering really is. Without a definition, the term to me is meaningless.

Engineers precisely specify a problem and then build a solution that's correct to within a tolerance. I'm afraid I don't see the resemblance to programming.

To expand on this. It is illegal in Canada for anyone without a proper engineering degree to call themselves an engineer. For example a computer scientist cannot call themselves an engineer while a computer or software engineer could.

I'm a ringed engineer; I think it's appropriate for non-ringed engineers to still self-identify by that title. An engineer is a person who engineers things.

There's a legal restriction on Professional Engineer and the P.Eng designation, but that's for very good reasons which have to do with liability and the protection of the public. That's a different beast, though, and in the general case "engineering" a solution to a problem is still engineering, whether or not you have a piece of paper telling you it is.

They share a common root (L. ingenium) but I'd hesitate to call them forms of the same word.

When you're talking about a profession though, engineer means something very specific. It means that you're trained and licensed and can be held legally responsible if whatever you're building should malfunction. Referring to your profession as an engineer when you don't meet those criteria is a bit disingenuous. It's akin to the difference between calling yourself a doctor because you went to medical school, and calling yourself a doctor because you got a PhD in english lit.

My hairdresser applies cleverness to solve the problem of making my hair look good, but I still wouldn't consider her an engineer.

This is a good point. Traditionally, engineering is more synonymous with structures, engines, tools etc. Where someone takes the prepared plans and develop the final product, they are referred to as a developer/builder/tool maker. Where (usually a team) e.g. architect/structural/mechanical/civil people etc.. work on the design/prepare the plan, they are referred to as engineers. Software developers or even software programmers take the prepared plan or design spec and write code. The software architect / software engineer (ausually a team also) etc.. are responsible for preparing the plan / design spec. Now to cap it all off - there is a middle ground - called an analyst/programmer who analyse, design and develop a solution. (The creative hair dresser - could also accommodate this spot middle ground).