The most common and most likely answer to this crossword clue is the 8 letter word SPECIOUS
I've seen this crossword clue in Financial Times
S
P
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C
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S
More clues leading to the result SPECIOUS
- Goggles, receiving promise to pay that’s deceptive
- Son cherished? Not right, but superficially plausible
- Dicky copies the Eye? Doubtful
- Rough copies, American, misleading
- False copies – forged, useless
- Phoney copies us, phoney looking good initially
- Misleading details about debt
- False son cherished — father ultimately coming out
- Showy glasses presented with note enclosed
- Questionable short detail on debt notices
Buddy explains!

The straight part
We know that "False" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case false = specious.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 SPECIOUS mean?
SPECIOUS adjective- Seemingly well-reasoned, plausible or true, but actually fallacious.
- Employing fallacious but deceptively plausible arguments; deceitful.
- Having an attractive appearance intended to generate a favorable response; deceptively attractive.
- Beautiful, pleasing to look at.