The most common and most likely answer to this crossword clue is the 7 letter word OSTLERS
O
S
T
L
E
R
S
Buddy explains!
The straight part
We know that "Grooms /l" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case grooms /l = ostlers.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 OSTLERS mean?
OSTLERS noun- A person employed at an inn, hostelry, or stable to look after horses; a groom