The most common and most likely answer to this crossword clue is the 7 letter word DRAGOON
I've seen this crossword clue in Financial Times
D
R
A
G
O
O
N
More clues leading to the result DRAGOON
- Press become tedious, with old content
- Fiery monster devouring old soldier
- Engineer ran good railroad
- Intimidating woman filled with love for cavalryman
- Heart of stone in witch, bully
- Continue guarding old soldier
- Drive past, over railroad
- Fearsome woman full of love for cavalryman
- Soldier feeding egg to fiery monster
- Soldier on after cutting tail from monster
Buddy explains!

The straight part
We know that "cavalryman" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case cavalryman = dragoon.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 DRAGOON mean?
DRAGOON noun- A horse soldier; a cavalryman, who uses a horse for mobility, but fights dismounted.
- A carrier of a dragon musket.
- A variety of pigeon.
- To force (someone) into doing something; to coerce.
- To surrender (a person) to the fury of soldiers.