Cryptic crossword clue
One banked on needing loco — did one? 6,6

The most common and most likely answer to this crossword clue is the 6 plus 6 letter word ENGINE DRIVER

I've seen this crossword clue in The Guardian
E
N
G
I
N
E
D
R
I
V
E
R

Buddy explains!

The straight part
We know that "did one?" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case did one? = engine driver.
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.

Crossword Answer definitions

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