The most common and most likely answer to this crossword clue is the 4 letter word CAPS
I've seen this crossword clue in The Daily Telegraph
C
A
P
S
More clues leading to the result CAPS
Buddy explains!

The straight part
We know that "Puts a limit on" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case puts a limit on = caps.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 CAPS mean?
CAPS noun- A close-fitting hat, either brimless or peaked.
- A special hat to indicate rank, occupation, etc.
- An academic mortarboard.
- A protective cover or seal.
- A crown for covering a tooth.
- The summit of a mountain, etc.
- An artificial upper limit or ceiling.
- The top part of a mushroom.
- (toy) A small amount of percussive explosive in a paper strip or plastic cup for use in a toy gun.
- A small explosive device used to detonate a larger charge of explosives.
- A bullet used to shoot someone.
- An international appearance.
- The top, or uppermost part; the chief.
- A respectful uncovering of the head.
- The whole top of the head of a bird from the base of the bill to the nape of the neck.
- The uppermost of any assemblage of parts.
- Something covering the top or end of a thing for protection or ornament.
- A collar of iron or wood used in joining spars, as the mast and the topmast, the bowsprit and the jib boom; also, a covering of tarred canvas at the end of a rope.
- A portion of a spherical or other convex surface.
- A large size of writing paper.
- A lie or exaggeration.
- To cover or seal with a cap.
- To award a cap as a mark of distinction.
- To lie over or on top of something.
- To surpass or outdo.
- To set an upper limit on something.
- To make something even more wonderful at the end.
- To select a player to play for a specified side.
- To shoot (someone) with a firearm.
- To select to play for the national team.
- To salute by uncovering the head respectfully.
- To deprive of a cap.
- To tell a lie.
- Capitalization.
- An uppercase letter.
- To convert text to uppercase.
- Capacitor
- A recording or screenshot.
- To take a screenshot or to record a copy of a video.
- A capsule of a drug.
- A wooden drinking-bowl with two handles.
- Capital letters; capitals.