The most common and most likely answer to this crossword clue is the 10 letter word ADULTERATE
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More clues leading to the result ADULTERATE
- Devalue time reduced in praise
- Doctor given praise about theory regularly
- Corrupt grown-up English count
- Corrupt love securing endless period
- Fully-fledged monarch took in food for doctor
- Corrupt deal utter shambles, article claimed
- Make impure drug, cutting what mature people pay
- Corrupt amount mature person has to pay to receive drug
- Grown up taking drug, cut with inferior ingredients
- Water down ale? True, tad disturbing
Buddy explains!

The straight part
We know that "Falsify" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case falsify = adulterate.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 ADULTERATE mean?
ADULTERATE verb- To corrupt.
- To spoil by adding impurities.
- To commit adultery.
- To defile by adultery.
- Tending to commit adultery.
- Corrupted; impure; adulterated.