Body Idioms
Emotional Idiom
Food Idiom
People Idiom
Animal Idiom
100

To see eye to eye

To agree with someone

100

To be over the moon

To be extremely happy

100

"Piece of cake!"

"That was easy!"

100

To have a heart of gold

To be kind and generous

100

To let the cat out of the bag

To reveal a secret

200

"Break a leg!"

"Good luck!" (Usually for theatre or performance.)

200

Feeling blue

Feeling sad

200

Cool as a cucumber 

Very calm and relaxed in a stressful situation

200

A team player

Someone who collaborates well in a group; someone who works well with others

200

"Hold your horses!"

"Wait a minute!" or "Be patient!"

300

To keep at arm's length

To avoid

300

To cry over spilled (spilt) milk

Getting upset about a mistake that cannot be changed.

300

In a nutshell

In summary; to explain something briefly

300

A smart cookie

A clever person

300

To cry wolf 

To exaggerate a problem

400

"It's on the tip of my tongue."

"I'm can't remember something, but I'm close."

400

Feeling under the weather

Feeling sick

400

In a pickle

In trouble

400

A jack of all trades

Someone who has many different skills

400

"You're barking up the wrong tree."

"You're trying to solve this problem the wrong way."

500

To give the cold shoulder 

To ignore someone

500

To be on pins and needles

To feel anxious or nervous while waiting for something to happen

500

The big cheese

A very important person

500

A chatterbox

Someone who talks a lot

500

To be in the doghouse

To be in trouble