Curious about bug and insect idioms? These expressions are buzzing with meaning and often pop up in everyday conversations. From phrases that describe annoyance to ones that symbolise transformation, insect-related idioms add colour and depth to the English language. Whether you’re preparing for IELTS, TOEFL, OET, Cambridge English exams, or PTE Academic, mastering these idioms will help you sound more fluent and natural. Explore this list to learn their meanings and how to use them like a pro!
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What are bugs and insects?
First things first, you all know what insects are right? If not, I’ll tell you…
Insects are very small creatures that usually have 6 legs and wings. They can be classed as ‘pests’ (think mosquito).
There are many idiomatic expressions (idioms) about bugs and insects. Are you ready to take a look?
bug and insect idioms list
Explore this list of bug and insect idioms with picture examples to help you understand their meanings and use them naturally in conversation.
Click here to find out the meaning of idiomatic/idiom (if you’re unsure)
ant idioms
An ant is a small but mighty insect that lives in colonies with thousands of others. They work together to build nests, gather food, and protect their queen. Ants are super strong for their size and can carry things much heavier than themselves.
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have ants in one’s pants
meaning – unable to sit still due to anxiousness, excitement, or nervousness
example – Sit down and be quiet. Do you have ants in your pants?
bee idioms
A bee or a bumblebee as they are sometimes called is a flying insect that makes honey. Bees aren’t aggressive and will only sting you if they feel threatened. The mean ones are called wasps and hornets. They are a similar but bigger and angrier.
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a busy bee
meaning – an active and busy person
example – Gary never stops, he’s such a busy bee.
have a bee in one’s bonnet
meaning – be obsessed with something
example – Leah has a bee in her bonnet about starting her own business.
make a beeline for someone/something
meaning – go directly towards someone/something
example – I made a beeline for the free bar as soon as it opened.
the bee’s knees
meaning – the best
example – I’ve treated myself to a new computer, it’s the bee’s knees.
the birds and the bees
meaning – sex education
example – My dad is talking to my little brother about the birds and the bees.
bug idioms
A bug is a general term for a small insect. e.g.
- Help, there is a bug in my bedroom.
- We need some pesticide; these little red bugs are eating my cabbages.
There is actually a good kid’s film called ‘A bug’s life‘ which can teach you the names of some common bugs. Children’s films are great for improving your English as the plot and the dialogue is fairly easy to understand.
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as snug as a bug in a rug
meaning – warm/cosy/comfortable
example – Let’s go home, get as snug as a bug and watch some films.
don’t let the bed bugs bite
meaning – wishing someone a good night’s sleep
example – It’s past your bed time, go upstairs now. Don’t let the bed bugs bite.
have the travel bug
meaning – have a strong desire/an urge to travel
example – I’ve had the travel bug for 10 years. I don’t think I’ll ever stop travelling.
butterfly idioms
A butterfly is a beautiful flying insect with colourful wings which sucks nectar from plants. A butterfly starts its life as a caterpillar until it forms a chrysalis and emerges as a butterfly.
I’ve always thought they should have been called a flutterby, as they daintily flutter by you.
Similar to a butterfly is a moth however they tend to come out at night and are not colourful more grey and brown colours.
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a social butterfly
meaning – a person who is sociable and friendly with everyone
example – Corey used to be a social butterfly, now he’s a recluse.
have butterflies in one’s stomach
meaning – your stomach feels funny because you are scared, nervous, anxious etc.
example – I had butterflies this morning, but they went just before the exam.
fly idioms
A fly is an insect with 1 pair of wings and compound eyes. They come in different sizes but are all annoying in my opinion (especially the ones that bite!).
Flies start their lives as maggots (a disgusting worm-like creature). Flies lay their eggs on rotting flesh; the maggots are born, and they pupate and emerge as flies.
If you like old school films…there’s a good one from the 80’s called ‘The Fly‘ about a guy who gets bitten by a fly, then turns into one.
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a fly on the wall
meaning – you would like to hear what is happening without being noticed
example – Marty is in trouble with his girl. I’d love to be a fly on the wall when she gets her hands on him.
drop like flies
meaning – people are dying, leaving, stopping an activity in large numbers
example – I’ve had three friends die in the last month. They are dropping like flies.
wouldn’t hurt a fly
meaning – a gentle, peaceful person or thing
example – My dog barks a lot, but she wouldn’t hurt a fly.
worm idioms
A worm is a long snake-like creature with no bones or limbs. They usually live in the soil however they can also live inside humans and animals as a parasite, yuck!
Did you know that ‘worm’ is also a verb (a regular verb)? It means to wriggle and crawl your way into or out of something.
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a bookworm
meaning – a person who loves reading
example – My mum has always been a bookworm, she’s always got her head in a book.
open a can of worms
meaning – do/say something that will cause more trouble than it’s worth
example – If the owner’s unqualified daughter gets the promotion, it will open a can of worms.
the worm has turned
meaning – someone retaliates against the person who has treated them badly
example – He treats her like shit. One day the worm will turn.
worm one’s way out of
meaning – give clever reasons to avoid doing something
example – We’ve wormed our way out of working this weekend, so we can come to the beach.
other bug and insect idioms
Now, let’s dive into a few quirky bug and insect idioms that don’t really fit into any particular category but are just as colourful and fun.
a face like a bulldog chewing a wasp
meaning – a very ugly face
example – Harley’s new girlfriend looks like a bulldog chewing a wasp.
knee-high to a grasshopper
meaning – very small/young
example – I haven’t seen Tara since she was knee-high to a grasshopper.
If you enjoyed learning about bug and insect idioms and expressions, why not click the buttons below to discover more picture idioms about animals.