There are a lot of words that you could use instead. See the link. (These are all adjectives describing a state of consciousness or physicality)
A word meaning to make sleepy/induce sleep is soporific.
The word shrewd means you are able to make good judgments and reasonable decisions. Antonyms would be obtuse, dull, or unknowing.
The word refreshing means new or fresh and different. An antonym is a word that means the opposite of the word you are using. Some antonyms of the word refreshing can be dull, boring, stale, or depressing.
Another word for dull and boring would be gloomy.
Yes, sleepy is an adjective, a word that describes a noun. Example: a sleepy baby.
Dull can be used as an adjective and a verb.
The word you are looking for is "stupefy". It means to make someone unable to think or feel properly, usually resulting in dullness or sleepiness.
The quick-witted boy was by no means dull.
Dull.
Thud.
The knife is to dull to cut anything.
drab
The word "Droning" means "to make a sustained low humming sound" or "to speak tediously in a dull monotonous tone." Example sentences: The woods were very quiet, except for the droning noise of insects. Listening to my teacher's droning voice makes me sleepy. The hours of droning speeches went on and on.
insipid
The Waray word for "sleepy" is "ginpipiraw."
tritest
The word shrewd means you are able to make good judgments and reasonable decisions. Antonyms would be obtuse, dull, or unknowing.
the root word is dull