The most common and most likely answer to this crossword clue is the 10 letter word EQUESTRIAN
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More clues leading to the result EQUESTRIAN
- Rider managed to cross island after end of late crusade
- Plea to have leader brought down, man on horseback
- Receiving pursuit, shake a rein of a horse
- Rider in crusade flanked by monarch and Scotsman
- Queen at start of race is changing jockey?
- Arnie misguidedly accepting mission on horseback
- Horse-rider requests trial, one totally unlimited
- Description of Queen’s trainerat work?
- Cavalier, upwardly mobile Keralite faces Internet challenge
- Rider‘s request upset Scotsman
Buddy explains!

The straight part
We know that "Cavalier" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case cavalier = equestrian.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 EQUESTRIAN mean?
EQUESTRIAN noun- An equestrian person; a horserider.
- Of horseback riding or horseback riders.
- Of or relating to the ancient Roman class of equites/equestrians