Bug vs. Insect: Why One Is Not Like the Other

, Staff Writer
Updated November 22, 2021
Bug - Cicada vs Insect - Bee
    Bug - Cicada vs Insect - Bee
    Cicada: Anuphong Panyamoon / iStock / Getty Images Plus / Bee: pic0bird / iStock / Getty Images Plus
    Used under Getty Images license

The word bug is applied broadly to describe any small creature belonging to the Insecta class and is often used interchangeably with insect. However, this is not necessarily correct. All bugs are insects, but not the other way around. Sound confusing? Explore the terms bug and insect, when and how to use them, and how to tell the difference.

The Difference Between Bugs and Insects

Bug is often used more casually while insect is seen in more academic contexts. However, that is not the extent of the difference between these critters. Insects are classified into classes and orders. All insects and bugs fall under the Insecta class. However, bugs are part of the Hemiptera order.

  • bug - small creatures belonging to the Hemiptera order with mouthparts made for piercing or sucking
  • insect - small invertebrate creatures belonging to the Insecta class that typically have three pairs of jointed legs and two pairs of wings

How to Use Bug Correctly

Bugs are a type of insect that belong to an order of insects called Hemiptera. They have mouthparts that can pierce or suck, long antennae, forewings that are thicker at the base and translucent at the top, and a chitinous exoskeleton.

Examples of bugs include bed bugs, stink bugs, cicadas, and many more. Funnily, not all creatures with “bug” in their name are actually qualified as bugs, including ladybugs.

  • A bug crawled up my leg.

  • I love bugs, but my friend hates them.

  • We have all kinds of bugs here in the summer.

Other Meanings of Bug

In addition to small, multi-legged creatures, bug has several other meanings.

  • There’s a bug in the system. (a flaw or imperfection)

  • I have a stomach bug, so I called in sick. (an illness)

  • The computer has a bug. (a virus or glitch)

  • The room is bugged. (surveillance with a concealed microphone)

  • My brother keeps bugging me. (annoy or bother)


How to Use Insect Correctly

Insects are small creatures with three-part bodies. Many of the creatures you may mistake for bugs are insects, including ants, bees, butterflies, grasshoppers, flies, fleas, mosquitoes, and more.

  • I was bitten by some kind of insect.

  • We used bug spray to repel insects.

  • Most insects hatch from eggs.

Classifying Insects

Insects are pancrustecean hexapod invertebrates belonging to the class Insecta and the kingdom animalia. There are over a million species of insects. Insects generally have the following:

  • chitinous exoskeleton

  • three-part body (head, thorax and abdomen)

  • three pairs of jointed legs

  • two pairs of wings

  • two or more eyes

  • one pair of antennae

But What About Arthropods?

To make matters even more confusing, many insects are classified as arthropods. In fact, more than 80% of all animals are classified as arthropods. The difference between arthropods, insects and bugs is that arthropods are a different type of phylum or subdivision that include spiders, centipedes, ticks and many others. Therefore, it is incorrect to classify these creatures generally as bugs or insects.


Know the Difference Between Words

Some bugs are classified by having clear wings. Learn to distinguish between transparent, translucent opaque. Additionally, some insects are poisonous, so brush up on the difference between poison and venom.