Oval
An oval is a shape. It is round but a bit longer in one direction. An oval can look like an egg or an ellipse.[1][2][3][4]
Oval shape and etymology
[change | change source]An oval is a flat (2D) shape that looks like an egg. According to etymology, the word “oval” comes from the Latin for “egg” (ovum).
Mathematical definition of an oval
[change | change source]Eggs in nature have many different shapes, so a mathematical formula should be able to describe many types of egg shapes.[5]
To describe an oval, we can use its four main measurements:[6]
- Length (L) – the total length of the oval.
- Maximum breadth (B) – the widest part of the oval.
- Shift of the maximum breadth (w) – how far the widest point is from the center along the long axis (usually x-axis).
- Breadth at one-quarter length (Dp) – the width at one-quarter of the length from the pointed end.
These four values help define the shape of the oval.
A mathematical formula[6] should be able to draw the oval using these parameters. To make calculations easier, the length is often set to 1 (L = 1). Then the other values are written as ratios:
- Shape index: B/L (which becomes B when L = 1).
- Asymmetry index: w/L (which becomes w when L = 1).
- Conicity index: Dp/B.
By changing these index values, we can create many different oval shapes. For example:[6]
- A circle has no asymmetry and equal length and width.
- An ellipse is longer than it is wide but still symmetrical.
- A classic egg shape is slightly asymmetrical.
- A pear-shaped (pyriform) egg has stronger asymmetry.
- A biconical shape (that is based on two oppositely oriented cones) has two pointed ends.
Some values can also produce shapes similar to a superellipse.[6] This is a particular family of closed curve like an ellipse. Specifically, it is a curve that lies between the ellipse and the rectangle as described elsewhere, for example, in the Martin Gardner Mathematical Games columns. Because the index values can vary a lot, this formula can describe many natural and geometrical shapes.
Notes
[change | change source]- ↑ 1911 Encyclopædia Britannica/Oval.
- ↑ "Oval Shape: Meaning, Properties, Construction, Examples". Cuemath: Geometry. Wilmington, DE, USA: CueLearn Inc. Archived from the original on 2026-03-27. Retrieved 2026-04-28.
- ↑ "Oval: Meaning of oval in English". Cambridge Dictionary. Cambridge, UK: Cambridge University Press & Assessment. 2026. Archived from the original on 2026-03-07. Retrieved 2026-04-28.
- ↑ Huerta, S. (October 2007). "Oval domes: History, geometry and mechanics" (PDF). Nexus Network Journal. 9 (2): 211–248. doi:10.1007/s00004-007-0040-3. eISSN 1522-4600. ISSN 1590-5896. Archived (PDF) from the original on 2012-04-13. Retrieved 2026-04-28.
- ↑ Dixon, R. (1991). Mathographics. Dover Recreational Math Series; General Science Series. New York, NY, USA: Dover Publications. ISBN 0486266397.
- 1 2 3 4 Narushin, V.G.; Orszulik, S.T.; Romanov, M.N.; Griffin, D.K. (April 2026). "What is an oval, officially and overall? Old and new mathematical descriptions". Computation. 14 (5) 101. Basel, Switzerland: MDPI. doi:10.3390/computation14050101. ISSN 2079-3197.
