The most common and most likely answer to this crossword clue is the 6 letter word FLIMSY
I've seen this crossword clue in The Guardian
F
L
I
M
S
Y
More clues leading to the result FLIMSY
- Delicate insect crossing one manuscript
- Thin female, horribly slimy
- Slim and painfully so in frilly coat
- Run across single copy lacking substance
- Very delicate insect wings I am studying primarily
- Lacking substance, travel around island on fringes of Mauritius …
- Fragile insect around is getting maiden hiding
- I’m second in race — not very strong at all
- Lightweight insect is caught nipping maiden
- Knowing about current manuscript lacking support?
Buddy explains!

The straight part
We know that "Thin" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case thin = flimsy.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 FLIMSY mean?
FLIMSY noun- Thin typing paper used to make multiple copies.
- A service certificate
- (in the plural) Skimpy underwear.
- A banknote.
- Likely to bend or break under pressure.
- Weak; ill-founded.