The most common and most likely answer to this crossword clue is the 12 letter word ANACHRONISMS
I've seen this crossword clue in The Daily Telegraph
A
N
A
C
H
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More clues leading to the result ANACHRONISMS
Buddy explains!
The straight part
We know that "Colts given to Normans, say" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case colts given to normans, say = anachronisms.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 ANACHRONISMS mean?
ANACHRONISMS noun- A chronological mistake; the erroneous dating of an event, circumstance, or object.
- A person or thing which seems to belong to a different time or period of time.