English Language & Usage Stack Exchange is a question and answer site for linguists, etymologists, and serious English language enthusiasts. Join them; it only takes a minute:

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

I came across something very similar to this in a thriller novel:

At this stage, the rocket is experiencing its maximum acceleration, say about ten gees.

Here, the author has spelled out the common military-pilot slang term for “gravitational force” using gee. However, as this term is an abbreviation, and is commonly treated as a unit of measurement (of acceleration) I'd have expected the written form to be g’s.

By analogy, I have heard people speak the unit “kilometer per hour” using the two-letter symbol for kilometer. However, I would expect this to be transcribed as “km per hour” versus “kay em per hour”.

Is this use of gee common? Is it correct?

share|improve this question
Gs as a simple plural should be without apostrophe, since it is an abbreviation or acronym. The apostrophe should be reserved for possessives and contractions. – bib Sep 24 '12 at 16:01
@bib One uses an apostrophe to make a plural of a single letter, because you cannot otherwise distinguish it from a separate word. If you have more than one letter i, then you have “several i’s”; you do not have “a few is”. See why? – tchrist Sep 24 '12 at 16:04
My dictionary lists gee for: an expression of surprise; command for a horse to go faster; a thousand dollars. – GEdgar Sep 24 '12 at 16:24
Remember in physics 'G' and 'g' are different so you need to make sure you use 'g' or "gee's" – mgb Sep 24 '12 at 16:28
Edit reverted and adjusted. g may not be a unit of measurement, but it may be considered a derived unit. It's not on to edit out a part of the OP's reasoning. – Andrew Leach Jan 16 at 11:43
up vote 9 down vote accepted

This Google Books search shows that gees is a perfectly common way to write out the abbreviation for the force of gravity. Here are a few of the relevant citations:

  • The outer four were all engineered to simulate gravity, in half-gee increments. Each layer consisted of three rings of ... The outermost triplet of rings was ten kilometres across and simulated gravity at two gees.
  • The clamshells and nanite foam filling were in place, sealing us against the pressures, cushioning us against the growing acceleration—more than ten gees and building.
  • We'd been boosting at half a gee, which isn't unpleasant. Two Mars gees would actually be three-quarters of an Earth gravity. Two-thirds Earth gees would be heavier than I like, but not nearly as onerous as Pismo Beach.
  • The idea that life might exist under the extremely rigorous conditions scientists predict on the surface of a neutron star — surface gravity 1011 gees, surface temperature 104 kelvin, and equatorial magnetic field strength 108 tesla — was first ...
  • Forward's novel, on the other hand, is of intelligent life on a neutron star with a radius of 10 kilometers and a surface gravity of 67 billion gees.
  • ... field and being in an equivalent accelerated frame of—it means that when the Anniversary is blasting five gees, the effect on us is the same as if it were sitting on its tail on a big planet, on one with five gees' surface gravity.”
  • One day the control shorted out in the rec. room and plastered the guests into the couch at 3 gees.
  • The gravity on the floor of level one was almost four and a half gees.
  • If there is no bounce and little room in which to decelerate, the magnitude of gee is so high as to be deadly. The force on an object due to Earth's gravity near Earth is equal to the mass of the body multiplied by 9.8 m/s2 (1 gee) and
  • number ot gees =1.0 32 ft/sec2 b F = 1.6 (1 lb) = 1.6 lb In Example 2-7 we introduced the term "gees" of gravity. When we state that a jet pilot experienced 4 "gees" we mean he felt four times the pull of gravity due to an acceleration or ...
  • And what we know today about gee forces proves that Ar-dan's dear adversary is absolutely right. A gee is a unit for measuring how rapidly a body's speed changes. One gee is the acceleration caused by gravity as a body falls near the ...
  • Then he felt gravity again as some force began to slow him down. The chair spun around so that Hackworth was looking up into the irregular constellation of chandeliers, and the acceleration shot up to several gees. Then back to normal.
share|improve this answer
+1 You know your As, Bs, Cs and gees. Whoops, I mean your A's, B's, C's and gees. – bib Sep 24 '12 at 19:30
@bib He who doesn't apostrophise letters doesn't know his As from a hole in the ground, Us from ugh. . . them, and Is in big trouble. (: – Zairja Sep 24 '12 at 20:17

The usual way to denote an acceleration of "ten gee" in technical writing would be 10g (lower case 'g'). Upper case 'G' usually denotes the Universal Gravitational Constant that appears in the law of gravitational attraction.

share|improve this answer

The absolutely critical thing is

do not - ever, ever, ever - use an apostrophe.

(Apostrophes have no connection to plural qualities.)

  1. "Gee" is great. Like fish or any class name in software engineering, the plural is the same as the single word.

  2. "Gees" is great. No problem here.

  3. Gs or gs is understandable, but there's no need for it. NOTE THAT the op mentions "and is in essence a unit of measurement" is completely wrong, a "g" is not a unit of anything. ("G" is totally unrelated.) "gee" (or perhaps "g") is just a cool slang term that aiviators use.

share|improve this answer
Hi. This is an old question, and other comments and answers have thoroughly dealt with the apostrophe-or-not issue. I am in the "yes, apostrophe" camp, but I respect your opposing point of view. I have rolled back your edit. – cobaltduck Jan 15 at 17:59
Hi cob! regarding the edit (apostrophe related), good call. However on the other issue, note that it simply is not a unit of measurement, in any way. (the first sentence on the wiki google is "The unit g is not one of the SI units", heh) So I did edit out that to avoid endless confusion. – Joe Blow Jan 15 at 20:39
Setting aside the edit issue. Going back to apostrophes. I would urge you to never use apostrophes in such a way. it is appalling to see them used in relation to plurals. (And the " ps and qs " is ridiculous, they're just ps and qs.) – Joe Blow Jan 15 at 20:41
Not an SI unit, and never claimed as such. However: 1g = 1 times the acceleration of gravity ~= 9.8 m/s/s; 10 g's or 10 gee = 10 times the acceleration of gravity ~= 98 m/s/s. So, yes, in some way of thinking it is a measurement. Nevertheless, I am not going to get into an edit war with you on a three-year-old question. Also, I am not the downvoter. – cobaltduck Jan 15 at 20:43
See Zairja's comment to tchist's answer. – cobaltduck Jan 15 at 20:57

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

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