LESS-THAN STELLAR
Hi, can you help me? I don`t understant the meaning of "less-than-stellar", and I don't know can I can use it.
This is my sentence: It's the responsability of doctors to help those who fell less-than-stellar to determine the underlying health issues.
Thanks!

Question

Answer

"Stellar" is a slang word for awesome/amazing/great. Less-than-stellar means the opposite: not stellar/not great. 
"It's the responsibility of doctors to help those who *don't feel great* to determine the underlying health issues."

I think a more common use for the word would be:
"The musician gave a stellar performance". (They gave an amazing performance).

Where I'm from (southwest US) it's not a word that's used very often in everyday conversations.

Answer

The meaning is that it is less than satisfactory or pretty mediocre

Answer

It means not great, or not ideal.

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