The most common and most likely answer to this crossword clue is the 7 letter word NAUGHTY
I've seen this crossword clue in The Guardian
N
A
U
G
H
T
Y
More clues leading to the result NAUGHTY
- Wicked US city accepting anything once!
- In Nanny’s case anything is bad
- Absolutely anything in the Big Apple is sinful
- Any old thing in New York is risqué
- Refusal to accommodate thug, unruly and rude
- Timeless “toy” that’s blue, like 26
- Any thug, possibly uncontrollable
- Disobedient in nothing, having little yen
- 28 Nothing yellow or blue
- Somewhat indecent and arrogant to change starter
Buddy explains!

The straight part
We know that "like 26" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case like 26 = naughty.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 NAUGHTY mean?
NAUGHTY adjective- Mischievous; tending to misbehave or act badly (especially of a child).
- Sexually provocative; now in weakened sense, risqué, cheeky.
- Evil, wicked, morally reprehensible.
- Bad, worthless, substandard.