Elliptic, Ellipsoid, Oval, Ovate, Obovate, Ovoid, Obovoid

elliptic [ ih-LIP-tik ] adjective: shaped like an ellipse

ellipsoid [ ih-lip-soid ] adjective: 3-dimensional in shape, where every cross-section is an ellipse

oval [ OH-vuhl ] adjective: broadly elliptical

ovate [ OH-veyt ] adjective: egg-shaped and flat

obovate [ ob-OH-veyt ] adjective: inversely ovate, with the narrower end at the base

ovoid [ OH-void ] adjective: egg-shaped

obovoid [ob-OH-void] adjective: inversely ovoid, with the narrower end at the base

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In everyday conversation, when a form resembles an egg, we simply describe it as egg-shaped. In botany, when plant parts are egg-shaped, they are described as ovate, obovate, ovoid, and obovoid. You have likely come across these terms if you have used plant identification guides or if you have read about the traits of plant families or individual plant species in published flora.

Ovate describes the shape of an upright egg that is two-dimensional, as in the flat blade of a leaf. In this case, the broader end is at the base of the leaf that attaches to the petiole or stem and the narrower end is at the top or apex of the leaf. In Latin, “ob” means opposite or reverse, so an obovate leaf resembles an upside-down egg where the narrower end attaches to the petiole or stem and the broader end is at the apex. Of the top 24 keystone and significant woody genera in the Mid-Atlantic Region—those that feed the most lepidopteran larvae—19 include species with ovate leaves. Of the almost two dozen different leaf blade shapes attributed to these genera, ovate is the most common. (See the chart here.) Although these terms are most widely used to describe the shapes of leaves and bracts, they also can apply to other “flat” plant parts, like petals, sepals, or tepals.

It is important to remember that leaf structure is not static. A leaf changes shape not only as it matures (read a brief explanation about how a leaf grows into its shape and size here), but also in response to environmental conditions, such as light intensity, water availability, temperature changes (Nakayama, 2024), wind exposure, herbivory-induced stress (Alves-Silva & Del-Claro, 2016), and competition between species. Leaves on the same plant may vary in shape, not only between basal and cauline (on the stalk) leaves, but even from one to the next along the same stem. For example, the compound leaves of native Fragaria virginiana (wild strawberry) typically have obovate leaflets, but sometimes it can produce leaflets that are oval to ovate (refer to the photographs above). One diagnostic trait that distinguishes it from relative Fragaria vesca (wood strawberry), in which ovate leaflets are more common, is that, no matter the shape of F. virginiana’s leaflets, their terminal tooth is usually smaller (shorter or narrower) than the adjacent teeth.

Ovate Leaves, Bracts, and Sepals

Left to right: Natives Betula nigra, Carya ovata, Swida (syn. Cornus) alternifolia, Viburnum dentatum, Pachysandra procumbens, Pycnanthemum muticum,  Trillium grandiflorum, and Claytonia virginica.

Obovate Leaves, Bracts, and Petals

Left to right: Natives Alnus serrulata, Lindera benzoin, Magnolia tripetala, and Baptisia australis, non-native Trifolium repens, and natives Benthamidia (syn. Cornus) florida, Magnolia virginiana, and Geranium maculatum.

Similar to the shapes of ovate and obovate are lanceolate, oval, and elliptic. The Flora of Virginia describes lanceolate as “narrower than ovate.” While many dictionaries define oval as having the shape of an egg, an ellipse is a specific geometric form that is a type of oval. When discussing leaf shapes, though, unlike ovate, obovate, and lanceolate, the widest parts of oval and elliptic leaves are typically located near the middle of the blade. An oval leaf resembles an elongated circle, with its width generally exceeding half its length. In contrast, elliptic leaves usually have a length-to-width ratio of about 2:1, with sides that are parallel or slightly curved. Some botanical sources describe oval leaves as broadly elliptic, while elliptic leaves are sometimes referred to as narrowly oval.

Lanceolate, Ovate, and Obovate Leaves Compared to Oval and Elliptic Leaves

Left to right: Differences between leaf blade shapes, and color photos of natives Amelanchier spicata, Viburnum prunifolium, Viburnum nudum, and Ostrya virginiana.

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Plant parts that are 3-dimensional and egg-shaped are described as ovoid. Again, the egg is upright so the broader end is at the base. In the reverse, obovoid, the narrower end is at the base. Ellipsoid is also 3-dimensional, “elliptic in long section and circular in cross section” (Weakley et al., 2012). These terms are often used in the descriptions of fruits and seeds, but they may also refer to the shape of flower anthers, buds, bulbs, corms, and the like. Studies of cultivated fruits found that several genes control growth forms. For example, “one of the most commonly utilized tomato fruit shape gene is OVATE” (Wu, et al., 2018). Ten of the top 24 woody genera in the Mid-Atlantic Region include species that have ovoid fruit. (See the chart here.)

Ovoid Fruits (Column 1), Ovoid or Ellipsoid Fruits (Column 2),
Obovoid Fruits (Column 3), and Ovoid Flower Buds (Column 4)

Top to bottom, Column 1: Natives Hypericum prolificum and Quercus michauxii and non-native Corylus avellana ‘Contorta;’ Column 2: Natives Benthamidia (syn. Cornus) florida, Nyssa sylvatica, and Lindera benzoin; Column 3: Non-natives Oenothera speciosa, Ficus carica, and Rosa ‘Dr. W. Van Fleet;’ Column 4: Natives Hibiscus moscheutos and Magnolia virginiana.

Note: Click on images to see enlarged photos, captions, and photo attributions.
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References

Alves-Silva E and Del-Claro K. 2016. Herbivory-induced stress: Leaf developmental instability is caused by herbivore damage in early stages of leaf development. Ecological Indicators. 61(2): 359-365. ISSN 1470-160X. doi:10.1016/j.ecolind.2015.09.036.

Argus GW, Eckenwalder JE. 1993+. Volume 7. Flora of North America North of Mexico [Online]. 25+ vols. New York and Oxford.  (accessed August 30, 2025)

Campbell CS, Burgess MB, Cushman KR, Doucette ET, Dibble AC, Frye CT, Phipps JB, Dickson EE, Rohrer JR, Lewis WH, Ertter B, Bruneau A, Alice LA, Goldman DH, Macklin JA, Moore G. 1993+. Volume 9. Flora of North America North of Mexico [Online]. 25+ vols. New York and Oxford. (accessed August 30, 2025)

Furlow JJ, Meyer FG, Nixon KC, Stone DE, Whittemore AT, Sherman-Broyles SL. 1993+. Volume 3. Flora of North America North of Mexico [Online]. 25+ vols. New York and Oxford. (accessed August 30, 2025).

Murrell ZE and Poindexter DB. 1993+. Volume 12, Flora of North America North of Mexico [Online]. 25+ vols. New York and Oxford. (accessed August 30, 2025)

Nakayama H. 2024. Leaf form diversity and evolution: a never-ending story in plant biology. Journal of plant research, 137(4): 547–560. doi: 10.1007/s10265-024-01541-4.

Strother JL. 1993+. Volume 6. Flora of North America North of Mexico [Online]. 25+ vols. New York and Oxford. (accessed August 30, 2025).

Vander Kloet SP. 1993+. Volume 8. Flora of North America North of Mexico [Online]. 25+ vols. New York and Oxford. (accessed August 30, 2025)

Wagner WL. 1993+. Oenothera speciosa. Volume 10. Flora of North America North of Mexico [Online]. 25+ vols. New York and Oxford. (accessed September 10, 2025)

Weakley AS, Ludwig JC, Townsend JF. 2012. Flora of Virginia. Botanical Research Institute of Texas.

Wu S, Zhang B, Keyhaninejad N, et al. 2018. A common genetic mechanism underlies morphological diversity in fruits and other plant organs. Nature Communications. 9, 4734. doi: 10.1038/s41467-018-07216-8.