The most common and most likely answer to this crossword clue is the 7 letter word MONARCH
I've seen this crossword clue in Financial Times
M
O
N
A
R
C
H
More clues leading to the result MONARCH
- Number turning up in protest — who don't republicans want?
- No turning back, engaged in troop movement for King?
- King against participating in military display
- Rally rounding on head of state
- Tramp banking on sovereign
- ‘Butterfly Month’ involves performing
- National leader performing in moving protest
- Working to break demo ruler
- After one short day chief becomes king?
- Ruler to walk clutching leg
Buddy explains!

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 MONARCH mean?
MONARCH noun- The ruler of an absolute monarchy or the head of state of a constitutional monarchy.
- The monarch butterfly, Danaus plexippus, and others of genus Danaus, found primarily in North America, so called because of the designs on its wings.
- (Aboriginal English) A police officer.
- (often capitalised) A stag which has sixteen or more points or tines on its antlers.
- The chief or best thing of its kind.