The most common and most likely answer to this crossword clue is the 8 letter word PLODDING
P
L
O
D
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The straight part
We know that "Like archetypal copper" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case like archetypal copper = plodding.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 PLODDING mean?
PLODDING verb- To walk or move slowly and heavily or laboriously (+ on, through, over).
- To trudge over or through.
- To toil; to drudge; especially, to study laboriously and patiently.
- Slow, laborious progress.
- Progressing slowly and laboriously.