The most common and most likely answer to this crossword clue is the 4 letter word DEER
I've seen this crossword clue in The Times
D
E
E
R
More clues leading to the result DEER
- Made error accommodating ruminant animal
- Does perhaps put off removing centrepiece
- Grass sent up for ruminants
- Does perhaps rush around
- Does perhaps rush around...
- Reportedly expensive source of venison
- Crossword puzzle the solver finally does, perhaps?
- A buck? That’s pricey by the sound of it!
- Does perhaps run after girl
- Does one river meet another?
Buddy explains!

The straight part
We know that "ruminants" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case ruminants = deer.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 DEER mean?
DEER noun- A ruminant mammal with antlers and hooves of the family Cervidae, or one of several similar animals from related families of the order Artiodactyla
- (in particular) one of the smaller animals of this family, distinguished from a moose or elk
- The meat of such an animal; venison.
- (except in the phrase "small deer") an animal, especially a quadrupedal mammal, as opposed to a bird, fish, etc.