The most common and most likely answer to this crossword clue is the 7 letter word MINIMUM
I've seen this crossword clue in The Guardian
M
I
N
I
M
U
M
More clues leading to the result MINIMUM
- Smallest musical note presented with hesitation
- Smallest skirt for mother
- Least quiet home I’m entering
- Note a little hesitation at the very least?
- Note what’s said when hesitating as little as possible
- Short piece of music you perform, ultimately, least
- Car’s quiet at least
- Note nearly everybody finds hardly noticeable
- A short dress, mother, to say the least
- The smallest skirt mother wanted
Buddy explains!

The straight part
We know that "Smallest" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case smallest = minimum.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 MINIMUM mean?
MINIMUM noun- The lowest limit.
- The smallest amount.
- A period of minimum brightness or energy intensity (of a star).
- A lower bound of a set which is also an element of that set.
- The smallest member of a batch or sample or the lower bound of a probability distribution.
- To the lowest degree.