The most common and most likely answer to this crossword clue is the 5 letter word LASSO
I've seen this crossword clue in The Guardian
L
A
S
S
O
More clues leading to the result LASSO
- Rope, behold, used to catch donkey?
- What cowboy uses, see, for catching animal
- Catch girl with Oscar
- Catcher ostracised initially after miss
- Restraint of girl leading to love
- Snare left like this
- Left donkey with ring and rope
- Catch up in Franco’s salon
- Look – animal has got caught! With this?
- Heading west, huge saddle’s dropped rope
Buddy explains!

The straight part
We know that "something catching" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case something catching = lasso.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 LASSO mean?
LASSO noun- A long rope with a sliding loop on one end, generally used in ranching to catch cattle and horses.
- An image-editing function allowing the user to capture an irregularly-shaped object by drawing an approximate outline.
- To catch with a lasso.