The most common and most likely answer to this crossword clue is the 5 letter word LASTS
I've seen this crossword clue in The Daily Telegraph
L
A
S
T
S
More clues leading to the result LASTS
Buddy explains!

The straight part
We know that "holds out" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case holds out = lasts.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 LASTS mean?
LASTS verb- To perform, carry out.
- To endure, continue over time.
- To hold out, continue undefeated or entire.
- A tool for shaping or preserving the shape of shoes.
- To shape with a last; to fasten or fit to a last; to place smoothly on a last.
- A burden; load; a cargo; freight.
- A measure of weight or quantity, varying in designation depending on the goods concerned.
- An old English (and Dutch) measure of the carrying capacity of a ship, equal to two tons.
- A load of some commodity with reference to its weight and commercial value.