The most common and most likely answer to this crossword clue is the 4 letter word MEEK
M
E
E
K
More clues leading to the result MEEK
- Under yours truly, every king initially submissive
- Timid male's reaction to mouse?
- Timid male reaction to mouse?
- Submissive maiden: ‘You’re scaring me’
- Submissive man evidently embarrassing kids, initially
- Almost run into front of Kate Humble
- Timid male, I’m frightened!
- William gave Kate rank, ultimately they will inherit!
- Like a mouse beginning to make fearful sound
- Setter and moose, left out among inheritors of the earth?
Buddy explains!

The straight part
We know that "submissive" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case submissive = meek.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 MEEK mean?
MEEK verb- (of horses) To tame; to break.
- Humble, non-boastful, modest, meager, or self-effacing.
- Submissive, dispirited.