Sciency Words: Acetic Acid (An A to Z Challenge Post)

Today’s post is a special A to Z Challenge edition of Sciency Words, an ongoing series here on Planet Pailly where we take a look at some interesting science or science related term so we can all expand our scientific vocabulary together. In today’s post, A is for:


Chemists have several different ways to define what an acid is (specifically, they have three definitions for acids and bases). But in many if not most cases, the key distinguishing feature of an acid is what I like to call a “dangling proton.”

By that I mean there’s a single proton (a.k.a. a hydrogen ion) sort of sticking off the side of the molecule. This proton is only loosely attached, and it could easily break off given the opportunity. With that in mind, I’d like you to mean acetic acid.

You probably know acetic acid best for its staring role in vinegar. Vinegar is a mix of water, acetic acid, and sometimes traces of other things for flavor.

I probably first heard about acetic acid in school, long before I had any reason to care about chemistry. It wasn’t until more recently, when I committed myself to learning this science stuff for the sake of becoming a better science fiction writer that I really found out what acetic acid is.

I decided to start the A to Z Challenge with acetic acid because the name illustrates something that I think is an important thing to know about scientific terms: some of them are kind of dumb. The “acetic” in acetic acid comes from the Latin word acetum, which means acid.

So acetic acid literally means “acid acid.” Not very creative, chemists.

Next time on Sciency Words: A to Z Challenge, we’ll find out what the deal is with the name brontosaurus.

38 thoughts on “Sciency Words: Acetic Acid (An A to Z Challenge Post)

      1. I guess it shouldn’t surprise me that the definition of “acid” isn’t straightforward. But it makes sense if you consider that we had the acid concept long before we knew anything about molecules or ions, and that our legacy categories rarely map seamlessly with subsequent scientific discoveries.

        Liked by 1 person

      2. That’s a very good point. I wish I’d brought that up. Quite a few of my A to Z posts will be about how we name things before we really understand them (that is, assuming I don’t get myself off track with this A to Z series).

        Liked by 1 person

    1. Awesome question! So acetic acid is an organic chemical, and a fairly ordinary (and boring) one at that. But learning about acetic acid was sort of a stepping stone for me on the path to learning about acids in organic chemistry, and ultimately to learning about amino acids.

      And once I started getting my head around amino acids, I was on my way to learning about the field of astrobiology–the scientific search for life on other worlds–which is definitely very useful to me as a science fiction writer.

      Also, astrobiology: that should be my A-word for next year.


      1. That’s very good to know. My lesson into acids was trying to make a good marinade, and really breaking it down to a science. Acetic Acid, usually in the form of vinegar, does play a part in marinades. When I’m not writing worldbuilding articles or stories, I’m usually cooking.

        Liked by 1 person

      2. Yeah, ever since I started studying organic chemistry, the kitchen has been a weird place for me. I keep thinking about how the stuff I learn relates to the stuff I’m cooking or the stuff I’m eating.


      3. I’ll be sure to do that. My chemistry studies have focused almost exclusively on organic chemistry. Metals don’t come up much, so that’s a huge chunk of the periodic table that I’m sort of missing.


  1. Wow. Great post. I really like the language side of science (and most things). I like that, “acid acid.” It’s differnet, but reminds me self-redundant things like “this is our *last and final* stop…” and “please follow all *rules and regulations*…” It’s good to know chemists have been doing it for at least as long as marketers and lawyers.

    Liked by 1 person

    1. I really love exploring the linguistics of science. That’s something that I always try to do with Sciency Words, though I don’t always feel like I hit the mark.


      1. Same here. I love the way words fit together, science or otherwise. If I remember right, I stumbled across your blog right around the same time I started writing my Word of the Week feature, so it was a cool moment of sort of subconscious collective collaboration (I’m not actually the sort of guy who would say something like that) for me. I like to come across a word and then travel along its path for a while, and see what other words are hiding in the bushes. It’s a cool thing to say “oh, right, this word comes from this Latin word, which means the same thing as this other, more familiar word.” The minute you see that connection, which might not have been obvious before, it kind of brings focus to a whole bunch of other words.

        Liked by 1 person

      2. Thanks! That means a lot to me, and I’ve learned a lot for your blog too. As much as I love space and astronomy, I’ve never been particularly good at finding stuff in the sky. I’m getting better at it in large part thanks to you.

        Liked by 1 person

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

This site uses Akismet to reduce spam. Learn how your comment data is processed.