The most common and most likely answer to this crossword clue is the 5 plus 3 plus 7 letter word STARS AND STRIPES
I've seen this crossword clue in The Guardian
S
T
A
R
S
A
N
D
S
T
R
I
P
E
S
More clues leading to the result STARS AND STRIPES
- Support military bands holding African state's flag
- Standard heroes possess grit alongside guts
- Sailor smooths voyage on board ship bearing European flag
- Standard of best beach rubbish close to piers
- Standard French author’s nonsense devoured by the famous
- Exotic satin dress strap Pole might display
- Standard celebs full of ‘beach bollocks’
- During marvellous tar sands trip espied colours of America
- Spartan dress, it’s becoming standard
- Flag up traders’ past sins
Buddy explains!
The straight part
We know that "colours of America" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case colours of america = stars and stripes.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.