Is an Onion a Vegetable?

Onions are a staple in many kitchens. They add flavour to dishes and can be used in a variety of recipes. But is an onion a vegetable? That’s the reason you’re here…right? 

The answer is not always clear-cut, but we will explore the topic in-depth in this article. 

We will take a look at what constitutes a vegetable, and whether or not onions fit into that category.

In a nutshell, onion plants do not fit the definition of fruit, and we cannot classify the entire plant as a bulb (because it also includes edible leaves), therefore onions can be classified as vegetables. So let’s find out how we came to this conclusion and explore the topic in more detail.

In this article, we will go into detail about onions in general and summarise why we came to this conclusion. 

By the end of this article, you will know everything there is to know about onions, onion seeds and why we believe they are vegetables. Let’s get started:

Is an Onion a Vegetable snippet image

Table of Contents

There is a mix of opinions on the internet

Before we get into the facts, allow us to explain how we ended up in this situation:

We came across a discussion forum on Reddit over the weekend whilst simultaneously watching onion-related videos on YouTube (sad we know). During this time of trawling through the vast wasteland of the Internet, we found several individuals on Reddit fiercely debating whether onions are vegetables or fruits. We found this topic fascinating because we’ve always referred to onions as a vegetable.

We don’t know about you, but we’ve always associated onions with vegetables, and we see them in the vegetable section of the supermarket when we go shopping. However, just as tomatoes are classified as fruits rather than vegetables since they are produced from a flower and contain seeds, we may be mistaken about onions.

To determine whether onions should be classified as fruits or vegetables, we must first identify the distinctions between fruits, vegetables, roots, and bulbs.

bulbous plants

Is An Onion A Root?

In order to determine whether or not an onion bulb is a root, we need to first understand what constitutes a root vegetable. A root vegetable is a plant that grows underground, and its edible part is the swollen and fleshy part of the stem that anchors the plant into the soil.

Some common examples of root vegetables are carrots, beets, potatoes, and ginger. Since onions do not grow underground but rather aboveground, they are not classified as a root vegetables.

Wikipedia defines a root in the following way, “Root vegetables are underground plant parts eaten raw by humans as food. Although botany distinguishes true roots (such as taproots and tuberous roots) from non-roots (such as bulbs, corms, rhizomes, and tubers, although some contain both hypocotyl and taproot tissue), the term “root vegetable” is applied to all these types in agricultural and culinary usage”.

onions root vegetables

Is An Onion A Bulb?

Now that we’ve established that onions are not roots, let’s move on to whether or not they can be classified as bulbs. According to the Merriam-Webster Dictionary, a bulb is “a usually rounded underground storage organ present in many flowering plants and composed of modified leaves enclosing one or more buds”.

Onions certainly meet this criteria since they are an underground storage organ (they store nutrients for the plant) and are composed of modified leaves. However, not all bulb vegetables are created equal, and there is another type of bulb called a true bulb. A true bulb is defined as “an underground storage organ that is more or less garlic-shaped, consisting of a short stem surrounded by fleshy scales or leaves”.

While onions are technically bulbs, they are not classified as true bulbs since they do not have a garlic-like shape. Therefore, we cannot classify onions as bulbs outright.

stem and scale leaves

Is An Onion A Fruit?

Fruits are defined as “the often sweet and fleshy reproductive body of a seed plant, typically consisting of enclosing ovaries that contain one or more seeds”.

Onions meet this criteria since they contain seeds, but onions also have a different type of fruit called an accessory fruit. Accessory fruits are defined as “fruits in which the edible part is not derived from the ovary but from some other parts of the flower, such as the receptacle (strawberry) or perianth (banana)”.

This means that while onions are could be classified as fruits, they are not the type of fruit that we typically think of when we think of fruits (such as apples and oranges). In this case, we wouldn’t class an onion or onion bulbs as a fruit.

plant species

Is An Onion A Veggie?

We’ve now established that onions are not roots, bulbs, or fruits so that only leaves us with one category – vegetables. Vegetables are defined as “a usually herbaceous plant (such as the cabbage, bean, or potato) grown for an edible part that is usually eaten as part of a meal”.

This definition certainly includes onions since they are herbaceous plants grown for their edible parts. Additionally, onions fit into the culinary definition of vegetables, which is “a usually green herb or other plant product used as a savoury ingredient of salads or cooked dishes”.

onion vegetable


After all this time we have spent looking over the onion debate with a fine-tooth comb, we think it’s time to draw up some decent conclusions. So, is onion a fruit, a vegetable, a root, a bulb, or anything else?

It is debatable, however. The onion plant itself is composed of numerous layers, each with its own distinct purpose. While the core and bulb are merely parts of the whole plant. “Fruits” and “vegetables,” for example, are more inclusive classifications of the edible plant parts.

Because the leaves are also edible, we believe it’s inaccurate to call the onion (the entire plant) a bulb, but we may say a bulb of onion when referring specifically to the fleshy part of the onion plant that grows in the ground.

In conclusion, because the entire plant is not a bulb and we can’t define it as fruit, onions are considered vegetables by us.

onion seeds develop

People Also Ask

Is onion a vegetable or herb?

A herb is any plant with leaves, seeds, or flowers that may be used for flavouring, food, medicine, or perfume. As a result, onions are nto classified as a herb but as a vegetable. Onion relatives include chives, garlic, shallots, scallion, and leeks.

Why is an onion a veggie?

Onions, like all onions, do not meet the definition of fruit since they do not develop from the flower portion of the plant. We can’t really put them in a category solely as bulbs because they are edible all throughout.

Can vegetarians eat onions?

Yes, vegetarians can eat onions since they are not classified as meat. Some people may choose not to eat onions because of their strong taste or smell. Onions are a type of vegetable that is composed of numerous layers, each with its own distinct purpose. The core and bulb are merely parts of the whole plant. “Fruits” and “vegetables,” for example, are more inclusive classifications of the edible flowering plant parts.

vegetarian meal
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