I have always differentiated a rectangle from an oblong by the oblong having rounded corners rather than sharp verticies, it is still rectangle shaped in every other way however.

I'm American (though living in a Commonwealth country) and I don't think I would naturally use the word oblong at all. It did take me a long second to remember whether an oblong would usually refer to a rectangle or an oval though, so that's an anecdata point in favor.

To me rectangle is a maths shape with complete straight sides and exact corners. Oblong is for something more organic and "lumpy" - although still basically a rectangle.

https://en.wikipedia.org/wiki/Talk%3AOblong,_Illinois

comment catcher!

Although I have a maths (BrE) degree I am no geometrician. In my personal usage, oblong=rectangle. I don't have a feeling that oblong is "longer", or really different in any other way - just a less formal name. In fact I found it surprising and interesting to read here that for many (most?) people there is a difference (the inclusion of the word "long" has always zipped past me!). I certainly never use the word oblong for ovals (although I now understand that that is a common and important meaning!).

I do, however, reserve the word "ellipse" for the conic section (it must satisfy ax^2 + by^2 = 1). Other things similar to ellipses would be "oval" - although they must, in my usage, still be approximately symmetrical in 2 perpendicular directions (so egg shapes don't count).

A bit of Googling suggests The Oval is named after the historic area of London in which it's based, which was named after its definitely ovular road layout, and not because of the shape of the playing area.

First time I'm hearing oblong to mean anything other than a rectangle (41 y/o from London). In my head oblong and rectangle mean slightly different things though, but I'm not sure I could explain how. Maybe it's more an aesthetic thing than a geometrical thing, oblong sounds more refined somehow.

I’m British, and for me oblong=rectangle; but I also would mean ellipse if I said oval. If I meant egg-shaped I think I would say ‘egg-shaped’.
Similar to cricket, a lot of Aussie rules football grounds are called ‘ovals’ and those are definitely supposed to be ellipses.

P.S. I assume the word "oval" comes from the word for egg, so I acknowledge that my requirement for symmetry is unreasonable and, presumably, incorrect! But part of the interest in language is about differences in usage.

Hello! I am the poster of the original thread (Ruth Ware). Someone on threads pointed me towards your blog and I thought it was very intrusive and in lie with my own assumptions about the UK meaning being a narrowing of the original definition.

To respond to your question about ovals and ellipses, I don't know if this is a UK wide thing, or just a personal definition, but to me, oval means roughly egg-shaped (which I take to be the etymology, presumably from ova). So that includes ellipses within certain parameters, but not, for example, cigar shaped ellipses. Those I would call an ellipse but not an oval. So it's not so much that an oval precludes an ellipse, but more that there are ovals which aren't ellipses, and ellipses that aren't ovals.

Finally one other point, my discovery arose from my realisation that my kids and I were using the word oblong differently. My son asked me to pass the "oblong bowl" and I replied that we didn't have one. "Oblong" is no longer taught in UK schools as far as I know, they use rectangle. So I think this has left a gap for the US meaning to drift across via social media. I wouldn't be surprised if in twenty years the US definition was the more common usage in the UK as well.

Thanks for an interesting follow-up!

For me (BrE, 50 something years old), I would probably never use oblong in general life, but if you pushed me on what it meant I would say a non-square rectangle. I certainly wouldn't think of anything with rounded corners as an oblong.

As to ellipse and oval, I would probably define oval as "a vaguely-squashed circle, with no specific dimensions, but despite the obvious egg derivation, not particularly egg-shaped - probably having two planes of symmetry rather than one". Meanwhile an ellipse is "the same as an oval but it's definitely got some specific mathematical definition that I don't know about". Ellipse definitely feels more "mathematics-y".

Old BrE speaker: for me rectangle and oblong are synonyms. But I do like the idea that it can distinguish non-square and square rectangles (even though I don’t think of squares as rectangles!)
I would use oval to mean any kind of stretched circular shape and reserve ellipse for the specific mathematical form.

40 year old BrE speaker here and oblong is the same as rectangle for me, I read the OP on Threads and was very surprised to hear it is used for rounded things in the US. Re oval I honestly don't know whether I'd describe an egg shape as an oval but my gut feeling is they should be symmetrical. I'm not familiar with ellipsis as a word for a shape at all though - to me it mostly means "..."

For me (Mid-50s AmE - Colorado), the oblong is all about aspect ratio. It's a shape that is distinctly longer than it is wide, so at least 3:2. A slightly elongated rectangle is not an oblong. It's also rectangle-ish, but need not be strictly so; an ellipse is not an oblong, but an oblong can have rounded or cropped corners, or edges that are a bit irregular or out of true.

I think this because my brain has latched into the "long" part of "oblong" as being significant, and because it wasn't taught to me as a formal geometry term, so my brain says its definition is informal.

There may also be some bleed from the word "obelisk"; because they're so similar, my brain wants an obelisk to be oblong, so the very long trapezoids that are the sides of the former must be allowed as examples of the latter.

Definitely "frown" all over again! For me, elderly, British, rather innumerate: rectangle=oblong=rectangle=/= square! They are all quadrilaterals, but a square has four sides of equal length, joined by right angles. An oblong or a rectangle (to me, they are synonyms) also has four sides joined by right angles, but two of the sides are longer than the other two (obviously the two equal sides are opposite each other). There are also kites and parallelograms, but let's not go there.....

46 year old British English* speaker here. I've always thought of "oblong" as being a rectangle, not any other sort of long shape.

That said, it has always felt like an informal term, and also old-fashioned, something from a previous generation, but that's just a feeling; I have no hard data on that!

*(I grew up in Wales and went to a Welsh language primary school, but I doubt that's affected my understanding of oblongs!)

Same for me. 73 and oblong has always a rectangle.

I'm 70+ and in California. AME seems to think of oblong as an adjective, while BRE considers it a noun. I've heard the noun usage here in the States, mostly for shapes that are approximately rectangles but maybe without right angles, but even then it would more likely be used as a modifier: an oblong field, an oblong building or room. Wasn't there a song about things that are longer than they are wide?

Huh, I'm American and I had never noticed that "oblong" can also include ovals; until today I would have said that it was just a rectangle, or at most a rectangle with rounded corners. (I don't remember "oblong" ever appearing in any math class.) But sure enough, there are plenty of oblongs in the Corpus of Contemporary American English that are definitely not rectangular: American footballs, lunar craters, pills, asteroids, tumors, faces and skulls, cucumbers, potatoes, melons, eggs (including fish and insect eggs), balloons, zeppelins.

I also saw some confusion in the corpus between "oblong" and "oblate". "Oblate" is a technical term for a spheroid with one axis shorter than the other two, like a pancake; it's opposed to "prolate", a spheroid with one axis longer than the other two, like a cigar. The Earth, and every other planet, is oblate, *not* oblong.

I'm 75 and in England. Oblong was the word for a rectangle in junior school. Basic trains sets came with an oval of track - straight sides with curved ends. I just checked the Walthers website (USA). They sell a train set which " Includes 14 track sections to build a 38 x 45" (0.96 x 1.1m) oval ".

I'm an American, and I don't normally use "oblong" as a noun. However, when I do encounter it as a noun, I expect the prototypical to be a rectangle (or near rectangle) with an aspect ratio significantly different from 1. On the other hand, the adjective "oblong," which I do use, has no connotations about what kind of shape it should be, except that (again), the aspect ratio should differ significantly from 1. As to "oval," I expect an oval to be oblate, have rounded corners, and to possess two planes of reflection symmetry (at least approximately; a bit of an egg shape is fine, but not too much).

Old-ish Australian here. Oblong was the primary school word for what became a rectangle in high school. No curves anywhere!
An Australian Rules football ground is an oval. Not egg-shaped; it is technically an ellipse, but ellipse not a word I use in normal speech.

Just came across this in the wild, in (American) author Steven Saylor's novel "Catalina's Riddle" (1993), set in ancient Rome, describing the shape of an unfolded toga:

"What seems so simple in its unfolded state—a very wide piece of thin white wool, cut into a roughly oblong shape—becomes devilishly intractable and takes on a life of its own when one attempts to make it into a respectable-looking toga."

Having genuinely no idea what "roughly oblong shape" might mean (or what shape an unfolded toga might be), I found this: http://www.novaroma.org/nr/Toga_%28Nova_Roma%29 – which might be described as a long rectangle with two rounded corners and two (very long) diagonal corners – maybe he is using it here to mean something between an oval and a rectangle?.

The Oxford Learner's Dictionary online makes the same US/UK distinction as the Cambridge one: the first definition is strictly a rectangle that isn't square, the second is "(North American English) any shape that is longer than it is wide".

And so do Oxford's most recent general dictionaries: the Oxford Dictionary of English (cited by Lynne Murphy in the post) covers British English and gives only the rectangle definition, while its counterpart, the New Oxford American Dictionary, gives the more general one, "having an elongated shape, as a rectangle or an oval".

This post fascinates me. I'm a 70-ish AME speaker (northeast U.S.). I have never considered an oblong to be a rectangle with sharp 90-degree corners. To me it has always been a rounded shape with an aspect ratio readily recognizable as being greater than 1:1. This old dog has a few new wrinkles in his brain.

50 yo Brit here. I actually remember a transition from being taught oblong in one school (a Steiner school where my teacher was an older man and very much not a maths person) and discouraged from using it in the next (in favour of rectangle; that was a conventional comprehensive). Which fits other commenters' sense of It being rather old-fashioned. It always meant the same thing, though, and this is the first I'm hearing of the alternative sense.

I'm American, in my 50s. I had no idea oblong could be used as a noun. I've never ever heard it used that way! So fascinating.

The subject of this thread reminded me of the 1844 Edgar Allan Poe short story The Oblong Box. The item in question was described thus: "It was about six feet in length by two and a half in breadth."

Terry Pratchett, the British author of satirical novels set in the Discworld, has the city’s “tyrant” operating out of the Oblong Office. I think the joke works best on the assumption that it’s *not* an oval, so at least the late-20th century British Pratchett thought of them as distinct shapes.

I (mid-40s Englishman) have "rectangle" and "oblong" as exact synonyms. A square isn't an oblong, true, but neither is a square a rectangle! I'm aware that it might be defined to be such in some maths classes, but to me that's a separate jargon usage for the word "rectangle", discrete from the normal word.

The one distinction that I would however make between the two words is that, while it still sounds perfectly natural in the mouth of anyone of any age, I tend to associate the word "oblong" much more with my parents' or grandparents' generations than with my own. I don't know if that temporal aspect was available in the data you were looking at?