What is salad, anyway?

    A local chain restaurant has signs saying, "Try our famous salad with chicken." Now, this strikes me as very foolish advertising, since unless you already know what they're talking about, you're going to say, "Isn't that a pretty pretentious way to say 'chicken salad'?" What they're talking about is an ordinary dinner salad with a piece of either fried or baked chicken on top. As I say, kind of poor advertising when it doesn't convey anything to people who don't know about the advertised product already.
    However, it leads me to a question, what the hell is a salad anyway? Chicken, egg and potato salads aren't particularly like the more common kind with lettuce and more lettuce and some more lettuce and a slice of tomato and some other stuff. It's usually cold or at least unheated and involves some kind of dressing and some kind of vegetables. It's usually a side dish or an appetizer, but there are dinner salads that serve as a main dish. So what's a salad?
    (Whatever you do, don't look it up on Wikipedia; they say pretty much what I just said except for throwing in a gratuitous "heterogeneous.") But Wikiland did help with one or two suggestions: that green thing with all the lettuce is a "garden salad" or "green salad." This suggests that a salad is a cold thing with vegetables in it, though that leaves out how I used to make egg salad. OK, a cold thing with spices, dressing or both. I'm not sure if the root world is salt (as we all once learned about "salary"; the Wikis say yes). Maybe it's a cold, salty thing with dressing. But famous with chicken.