The idiom "sick as a dog" means feeling very sick or ill. It is often used to describe someone who is experiencing severe symptoms of an illness or a hangover.
The origin of this idiom is not clear, but it is believed to have originated from the idea that dogs are known to eat anything they find, including spoiled food or garbage, which can make them sick. Therefore, when someone says they are "sick as a dog," they mean they feel as bad as a dog that has eaten something it shouldn't have.
You can use this idiom in a sentence like this: "I can't come to work today because I'm sick as a dog." Or, "After drinking too much last night, I woke up feeling sick as a dog."
Overall, "sick as a dog" is a common idiom used to describe feeling very sick or unwell, often due to an illness or excessive drinking.
• I caught a cold last night and woke up feeling sick as a dog this morning.
• After eating that seafood, I felt sick as a dog for the whole night.
• I was so nervous before my big presentation that I felt sick as a dog.
• I ate too many sweets at the party and now I feel sick as a dog.
• It was a horrible flu, and I felt sick as a dog for two weeks.
• My friend drank too much alcohol last night and now she's sick as a dog.