The most common and most likely answer to this crossword clue is the 12 letter word ROLLER-SKATE
I've seen this crossword clue in The Guardian
R
O
L
L
E
R
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S
K
A
T
E
More clues leading to the result ROLLER-SKATE
Buddy explains!

The straight part
We know that "wheel herself along" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case wheel herself along = roller-skate.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 ROLLER-SKATE mean?
ROLLER-SKATE noun- A boot having small wheels or casters attached to its sole; used for roller skating