An idiomatic expression is a word used that has a deeper meaning than the one in the dictionary or in the glossary.
Examples:
All sizzle and no steak
A thing/person which fails or you're disappointed with.
Beats me
You cannot understand something.
Bite off more than you can chew
Try to do more than you are able to do.
Burst one's bubble
To destroy someone's sense of well-being.
Butter somebody up
To flatter someone
Couch potato
A person who has a great deal of time watching television.
Skeleton's in the closet
To reveal secret information carelessly.
Spill the beans
Tell the secret.
Under the weather
Being unusual because you're sick.
Walking on eggshells
To try very hard not to upset someone.
Down on the dump
Being sad or unhappy
Knock yourself off
To amaze someone
Pulling leg
Joking or to tease someone.
Knock off the socks
To impress
Load of baloney
A nonsense
Monkey business
A deceitful behavior or being mischievous
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