If I say,

"I have a functional understanding of car engines"

does this convey:

  1. I understand how car engines function (this is what I originally thought)
  2. My understanding of car engines is functional (which doesn't make much sense, but what I suspect is correct)

So if I wanted to tell someone I understand how a car engine functions, I would say:

"I understand how a car engine functions"

and not:

"I have a functional understanding of car engines"


Functional literacy for example means reading and writing skills that are adequate "to manage daily living and employment tasks that require reading skills beyond a basic level."* That is, you can function.

If you have a functional understanding of car engines, you understand them well enough to do your job (maintaining or perhaps repairing them). You may or may not understand how they themselves function. You can have a functional understanding of something that doesn't itself "function" at all (mathematics, for example, or history).


These phrases align with similar "types" of knowledge; such as book smarts, intelligent on paper, lab smart. Both working knowledge and functional knowledge and the ones above have to do with the less "experienced" forms of knowledge. If you only know 'how it functions' that isn't of too much use if you don't know how it gets fixed.

They make up a spectrum if you will, where on one side you have book smarts from books and on the other side bunker/street smarts earned through experience. Working and functional knowledge seem like they would fall somewhere in the middle; you can talk about how a car works, discuss what something means, but you don't live and breathe that knowledge yet.

You have some grease on your hands, but none under your nails.


In the sense that functional means "capable of function" or "working" I think you could say one can have a "functional understanding" of car engines. That might include understanding how car engines function, but if you wanted to make that clear this is not the sentence to use.

Better would be to say you have a "working knowledge" of car engines. You know how they work, and you might even be able to fix one to some degree.

  • I think "working knowledge" is commonly used, but still, doesn't it technically mean that your knowledge is working, and nothing more?
    – sooprise
    Apr 14 '11 at 19:55
  • 1
    No, it doesn’t, any more than “rock-climbing experience” means that your experience is climbing rocks. Apr 15 '11 at 4:00
  • 1
    Experience itself doesn't climb, of course. You wouldn’t say that a sightseeing trip sees, either, or that a shopping bag shops, or that a rocking horse is simply a horse that is rocking. (It’s a horse-shaped toy that can rock.) Apr 15 '11 at 4:16
  • 1
    Using the word technically makes it sound like there is a simple rule — verbing noun means noun that is verbing — that determines the meaning of such a phrase, and if we use such a phrase to mean something else, we have (technically) misspoken. What I’m saying is this: that simple rule is wrong. Phrases like shopping bag and working knowledge that contradict that rule are correct. (The real rules are not so simple.) Apr 15 '11 at 4:24
  • +1 +1 +1, ok, those are great examples that break my argument. Now, can you direct me to what the real rules are? I'm interested to learn more.
    – sooprise
    Apr 15 '11 at 13:07

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.