The most common and most likely answer to this crossword clue is the 7 letter word SIDECAR
I've seen this crossword clue in The Times
S
I
D
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C
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R
More clues leading to the result SIDECAR
- Dash up with chap's cocktail
- Cocktail made with brandy, as cider awful
- Cocktail Mark consumes something fishy
- Switch raised, locking a hundred in passenger compartment
- Cocktail attachment
- Passenger vehicle was competitive, and is in reverse
- Teacher drinking endless coffee, one on a motorbike?
- Poor Cressida dropped small cocktail
- Some vehicle driven fast is going uphill
- Alcoholic drink is for the non-driver
Buddy explains!

The straight part
We know that "cocktail" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case cocktail = sidecar.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 SIDECAR mean?
SIDECAR noun- A one-wheeled attachment to a motorcycle to allow for a separate seat for a passenger or cargo space.
- A cocktail made with cognac (or brandy), triple sec liqueur, and lemon juice.