The most common and most likely answer to this crossword clue is the 3 plus 5 letter word TEA CHEST
I've seen this crossword clue in Financial Times
T
E
A
C
H
E
S
T
More clues leading to the result TEA CHEST
- Schools with prime requirement for ticking box
- Leaves box and coaches close to street
- River carrying long container
- Leaves box made of pine wrapped in paper
- Coaches beginning to transport container
- Drills type of junction box
- For every person involved in trial, it’s a big case
- Train set’s broken case
- Leaves boxing as a result of painful ordeal
- Box transported primarily behind coaches
Buddy explains!

The straight part
We know that "Leaves boxing" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case leaves boxing = tea chest.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.