The most common and most likely answer to this crossword clue is the 3 letter word SKI
I've seen this crossword clue in The Times
S
K
I
More clues leading to the result SKI
- Long blade in swordsman’s kit
- Runner starts to sprint, keeping improving
- Extremely sick, I go downhill fast
- Runner seen in Lusk Island
- Runner is going back to protect king
- Runner at last conquers Karakoram peak
- Slide and almost lose control of car
- Runner, 21, failing to finish
- Short fleece for runner
- Leave out short piece of winter sports equipment
Buddy explains!

The straight part
We know that "piece of winter sports equipment" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case piece of winter sports equipment = ski.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 SKI mean?
SKI noun- One of a pair of long flat runners designed for gliding over snow or water
- One of a pair of long flat runners under some flying machines, used for landing
- To move on skis
- To travel over (a slope etc.) on skis; to travel on skis at (a place), (especially as a sport)