1
general::
Eager and alert, as in Here is my new kindergarten class, all bright-eyed and bushy-tailed. The allusion here is to the appearance of a squirrel, which with its beady eyes and bushy tail looks ready for anything. [1930s]
American Heritage Idioms
2
general::
Phrase(s): bright-eyed and bushy-tailed
Fig. awake and alert. (Often used ironically, as in the first example. The idea is that one is like a frisky animal, such as a squirrel.) • Jill: Hi, Jane! How are you on this beautiful morning? Jane: Bright-eyed and bushy-tailed, just as you might expect, since I’ve only had three hours of sleep. • Despite the early hour, Dennis was bright-eyed and bushy-tailed.
McGrawhill's American Idioms And Phrasal Verbs