Question

Sitting Duck someone or something likely to be attacked and unable to put up a defense

Accepted Answer

Don't stay by yourself in the school yard after school. You'll be a sitting duck for all the bullies. A duck hunter knows that if a duck is sitting still, it's a much easier target than a duck in flight. By the first half of the 20th century, the phrase "sitting duck" was transferred to any person who was an easy mark for someone who wanted to cheat or do him or her harm.

Idiom	Sitting Duck
Example	Don't stay by yourself in the school yard after school. You'll be a sitting duck for all the bullies.
Meaning	someone or something likely to be attacked and unable to put up a defense
Origin	A duck hunter knows that if a duck is sitting still, it's a much easier target than a duck in flight. By the first half of the 20th century, the phrase "sitting duck" was transferred to any person who was an easy mark for someone who wanted to cheat or do him or her harm.

Duck Sitting Stay School Yard Bullies Attacked Unable