The most common and most likely answer to this crossword clue is the 2 plus 6 letter word NO CHANCE
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More clues leading to the result NO CHANCE
- Can he con criminal? Most unlikely!
- Tea during the present time? That's definitely out
- Can he con criminal? Absolutely not!
- That will not happen if small number gamble
- Leap in the dark after small number? Not likely!
- Zero probability? Certainly not!
- Can keep husband in, once free will go around — not possible
Buddy explains!

The straight part
We know that "Certainly not!" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case certainly not! = no chance.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.