Bright-Eyed and Bushy-Tailed

Etymology:

• This idiom was used in the 19th century, which referred to furry animals having bushy tail. It is seen that the tails of these animals go up when they are excited. Bright eyes represent cheerfulness and being alert. Both of the terms were combined and used in a single idiom. Most of the writers used this term to describe a very good state of someone. It was used in literature and poetry.