The most common and most likely answer to this crossword clue is the 5 letter word SILKY
I've seen this crossword clue in The Daily Telegraph
S
I
L
K
Y
More clues leading to the result SILKY
Buddy explains!
The straight part
We know that "Smooth" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case smooth = silky.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 SILKY mean?
SILKY noun- A seal which can magically transform into a human by shedding its skin.
- A chicken of a certain breed with very fine, silk-like feathers.
- Similar in appearance or texture (especially in softness and smoothness) to silk.
- Smooth and pleasant; seductive.
- Covered in long, slender, glistening hairs pressed close to the surface; sericeous.