The most common and most likely answer to this crossword clue is the 8 letter word SANGUINE
S
A
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More clues leading to the result SANGUINE
- In a little Nissan, Guinevere is cheerful
- Cheerful and not daft, consuming a half of stout
- Cheerful article penned by disturbed genius
- Upbeat article penned by troubled genius
- Rosy is sober having downed half of stout
- Bloody hospital! £1.05 to get toe removed
- Confident and with good reason, drinking half of Guinness
Buddy explains!

The straight part
We know that "Confident" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case confident = sanguine.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does SANGUINE mean?
SANGUINE noun- Blood colour; red.
- Anything of a blood-red colour, as cloth.
- A tincture, seldom used, of a blood-red colour (not to be confused with murrey).
- Bloodstone.
- Red crayon.
- To stain with blood; to impart the colour of blood to; to ensanguine.
- Having the colour of blood; blood red.
- Having a bodily constitution characterised by a preponderance of blood over the other bodily humours, thought to be marked by irresponsible mirth; indulgent in pleasure to the exclusion of important matters.
- Characterized by abundance and active circulation of blood.
- Warm; ardent.
- Anticipating the best; optimistic; confident; full of hope.
- Full of blood; bloody.
- Bloodthirsty.