Main Page

Explain xkcd: It's 'cause you're dumb.
Revision as of 13:12, 29 October 2013 by Jeff (talk | contribs)
Jump to: navigation, search

Welcome to the explain xkcd wiki! Today, the wiki is in read-only mode to allow for a hosting migration. Please enjoy reading all our xkcd explanations. We have an explanation for all 2 xkcd comics, and only 0 (0%) are incomplete. Help us finish them!

Latest comic

Go to this comic explanation

I'm working on assembling a combination declinometer, sclerometer, viscometer, aleurometer, stalagmometer, and hypsometer. I'm making good progress according to my ometerometer, a device which shows the rate at which I'm acquiring measurement devices.
Title text: I'm working on assembling a combination declinometer, sclerometer, viscometer, aleurometer, stalagmometer, and hypsometer. I'm making good progress according to my ometerometer, a device which shows the rate at which I'm acquiring measurement devices.


Ambox notice.png This explanation may be incomplete or incorrect: Please edit the explanation below and only mention here why it isn't complete. Do NOT delete this tag too soon.

Here, Megan is talking to Cueball about hygrometers. But before she can even finish explaining what it does, Cueball has looked up, found, and purchased the product. A hygrometer is an instrument for measuring the amount of water vapor in the atmosphere, or the amount of water in solids such as soil or wood.

It seems Randall (as Cueball) loves being able to measure things and therefore finds instruments or measurement tools that end in -ometer very interesting, and wishes to own all of them. Many measuring instruments use the suffix -meter which is derived from the Greek noun μέτρον for "measure". The character "o" always belongs to the first term, but it also belongs to old Greek words like thermo-meter, micro-meter, or even hygro-meter. Other measurement devices such as speedometer use an English word with an "o" appended to mimic the Greek derived terms, purportedly for easier marketing. Because themes in science often based on Greek terminology that ending at the first part appears often. Nonetheless Randall believes that this "o" belongs to the general term for measuring devices.

In the title text the author Randall states he is working on assembling a collection of measuring instruments. The list consists of:

  • A viscometer is an instrument to test the viscosity (ease of pouring) of a liquid. For example, honey has higher viscosity than water.
  • An aleurometer is an instrument to evaluate the quality of flour for baking by measuring how much a wet mass of wheat can expand when heated, while keeping its adhesivity.[1]
  • A stalagmometer is an instrument to measure surface tension of fluids by producing a drop and weighing it - the bigger the drop is, the larger surface tension the fluid has.
  • The word hypsometer can mean two unrelated instruments to measure height. One measures heights of a building or a tree by triangulation. The other measures altitude by measuring air pressure through its effect on the boiling temperature of water. It should not be confused with the altimeter which measures altitude by mechanically measuring air pressure (and which also does not follow the -ometer rule and might therefore be of less interest to Cueball? Is that the reason why Cueball appears in a diagram at the Wikipedia page for hypsometer but not for altimeter?).
  • An ometerometer, being a concatenation of -ometer with itself, would be a device for measuring measuring devices.


[Megan and Cueball are walking and talking. Cueball is holding his phone with one hand, looking at it.]
Megan: ...A hygrometer is a device for measuring—
Cueball: I want one! Ooh, found one for $7.99 with free shipping! I'm buying it.
Megan: —Humidity.
Cueball: Oh, cool!
[Caption below the frame:]
For some reason, I feel a powerful compulsion to own any device whose name ends in "-ometer."

Is this out of date? Clicking here will fix that.

New here?

Last 7 days (Top 10)

Lots of people contribute to make this wiki a success. Many of the recent contributors, listed above, have just joined. You can do it too! Create your account here.

You can read a brief introduction about this wiki at explain xkcd. Feel free to sign up for an account and contribute to the wiki! We need explanations for comics, characters, themes, memes and everything in between. If it is referenced in an xkcd web comic, it should be here.

  • List of all comics contains a table of most recent xkcd comics and links to the rest, and the corresponding explanations. There are incomplete explanations listed here. Feel free to help out by expanding them!
  • If you see that a new comic hasn't been explained yet, you can create it: Here's how.
  • We sell advertising space to pay for our server costs. To learn more, go here.


Don't be a jerk. There are a lot of comics that don't have set in stone explanations; feel free to put multiple interpretations in the wiki page for each comic.

If you want to talk about a specific comic, use its discussion page.

Please only submit material directly related to —and helping everyone better understand— xkcd... and of course only submit material that can legally be posted (and freely edited). Off-topic or other inappropriate content is subject to removal or modification at admin discretion, and users who repeatedly post such content will be blocked.

If you need assistance from an admin, post a message to the Admin requests board.