The most common and most likely answer to this crossword clue is the 11 letter word AVANT-GARDE
I've seen this crossword clue in The Guardian
A
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More clues leading to the result AVANT-GARDE
- Futuristic art gave Dan shivers!
- A vehicle finally left US yard, almost boldly innovative
- Original advantage involved in capturing king
- A danger with a TV broadcast that’s cutting-edge
- A garden set with a TV? That's unconventional
- Innovative smash! Advantage Leander finally
- Experimental version of Bible, different and great
- Radically new vat, a danger if misused
Buddy explains!

The straight part
We know that "that’s cutting-edge" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case that’s cutting-edge = avant-garde.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 AVANT-GARDE mean?
AVANT-GARDE noun- The vanguard of an army or other force.
- Any group of people who invent or promote new techniques or concepts, especially in the arts.
- Innovative, pioneering, especially when extremely or obviously so.