The definition of groggy is a state of being out-of-it or dazed due to being sick or tired.(adjective)
If you've just gotten off of a 10-hour plane trip and you've been awake all night, this is an example of when you would be described as groggy.
See groggy in Webster's New World College Dictionary
See groggy in American Heritage Dictionary 4
adjective grog·gi·er, grog·gi·est
Origin: From grog.
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