The most common and most likely answer to this crossword clue is the 6 letter word SUPERB
I've seen this crossword clue in The Times
S
U
P
E
R
B
More clues leading to the result SUPERB
- First class traveller confined to public transport on retirement
- Smashing up a Balkan’s fencing
- Splendid salesman aboard bus heading west
- Traveller in coach, returning first class
- Choice evening meal half-heartedly offered by British
- Grand pubs prepared to welcome monarch
- First rate drink, with ‘yssop, for example
- Splendid agent aboard coach going north
- Brill for each coming aboard U-boat
- . European belts up A1
Buddy explains!

The straight part
We know that "Splendid" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case splendid = superb.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 SUPERB mean?
SUPERB adjective- First-rate; of the highest quality; exceptionally good.
- Grand; magnificent; august; stately.
- Haughty.