The most common and most likely answer to this crossword clue is the 11 letter word SQUANDERING
I've seen this crossword clue in Independent
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More clues leading to the result SQUANDERING
Buddy explains!

The straight part
We know that "Wasting" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case wasting = squandering.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 SQUANDERING mean?
SQUANDERING verb- To waste, lavish, splurge; to spend lavishly or profusely; to dissipate.
- To scatter; to disperse.
- To wander at random; to scatter.
- The act by which something is squandered; wastage.