American Idioms

“Bite the bullet” – to face a difficult situation or make a difficult decision
“Bend over backwards” – to make a great effort to help or accommodate someone
“Break a leg” – a superstitious way of wishing someone good luck
“Cost an arm and a leg” – to be very expensive
“Get cold feet” – to become nervous or unsure about something
“Get the ball rolling” – to start something
“Hit the nail on the head” – to exactly correct or precise in an observation or statement
“In the same boat” – to be in the same situation as someone else
“It’s a piece of cake” – something is very easy to do
“Kill two birds with one stone” – to achieve two things with a single action
“Let the cat out of the bag” – to reveal a secret
“Not play with a full deck” – to not be mentally sound
“Out of the frying pan into the fire” – to move from a bad situation to a worse one
“Over the top” – excessive or extreme
“Rain on someone’s parade” – to spoil someone’s plans or good mood
“Throw in the towel” – to give up or surrender
“The ball is in your court” – it’s your turn to make the next move or decision
“The bee’s knees” – something is exceptional or the best
“The bottom line” – the most important or decisive factor
“The whole nine yards” – everything or all of it
“Under the weather” – feeling sick or unwell
“Up in the air” – uncertain or unresolved
“Wear many hats” – to have many different roles or responsibilities
“When pigs fly” – something is never going to happen
“You can’t judge a book by its cover” – appearances can be deceiving
“You can’t have your cake and eat it too” – you can’t have both at the same time
“You can’t make an omelette without breaking eggs” – some sacrifices are necessary to achieve a goal.
“You can’t take it with you” – material possessions are not important in the long run.
“You can’t teach an old dog new tricks” – it’s hard to change someone’s habits or ways of thinking.
“You can’t have the best of both worlds” – you have to choose one option over the other.

Australian Idioms

As bold as brass – meaning very bold and confident.
As busy as a one-armed paperhanger – meaning to be very busy.
As cold as a witch’s tit – meaning very cold.
As cool as a cucumber – meaning to be very calm and collected.
As dry as a bone – meaning extremely dry, usually referring to weather or the Australian landscape.
As easy as falling off a log – meaning to be very easy to do.
As flash as a rat with a gold tail – meaning to be very showy and flashy.
As game as Ned Kelly – meaning to be very brave and willing to take risks.
As happy as a sandboy – meaning very happy and content.
As mad as a cut snake – meaning to be very angry.
As right as rain – meaning to be in good health or to be doing well.
As scarce as hens’ teeth – meaning to be very rare or hard to find.
As slow as a wet week – meaning to be slow, either in terms of progress or movement.
As stiff as a board – meaning to be very stiff or rigid.
As strong as a Mallee bull – meaning to be very strong and resilient.

British Idioms

A piece of cake – easy or effortless task
A rain check – postponing an offer or invitation to a later time
To be a bad egg – to be a bad person
To be a bit of a dog’s dinner – to be a mess or disorganized
To be a bit of a lad – to be a young man who likes to have fun
To be a breath of fresh air – to be a pleasant change
To be a bull in a china shop – to be clumsy or destructive
To be a bundle of nerves – to be very anxious or nervous
To be a case in point – to be a good example of something.
To be a cat among the pigeons – to cause trouble or confusion
To be a cat’s whiskers – to be the best or the greatest thing
To be a chicken – to be afraid or frightened
To be a dark horse – to be an unknown person who performs exceptionally well
To be a drag – to be boring or unpleasant
To be a fish out of water – to be in an unfamiliar or uncomfortable situation
To be a flash in the pan – to be a short-lived success
To be a good egg – to be a good person
To be a gooseberry – to be an unwanted third person in a couple’s company
To be a lion in winter – to be old but still powerful
To be a pain in the neck – to be annoying
To be a red herring – to be a misleading distraction
To be a right Charlie – to be a foolish or foolishly act
To be a snake in the grass – to be a treacherous person
To be a square peg in a round hole – to be unsuited or inappropriate
To be a stick in the mud – to be dull or unadventurous
To be all mouth and trousers – to talk a lot but do nothing
To be barking up the wrong tree – to be pursuing a mistaken or misguided course of action
To be in two minds about something – to be indecisive
To cost an arm and a leg – to be very expensive
To have the last laugh – to triumph in the end