9 across
Climb
in
a
second,
somehow
dropping
nothing
(6)
Climb in a second, somehow dropping nothing (6)
hints
0
checks
0
hints
The definition is at the beginning of the clue.
How the clue works
The definition is Climb — straightforward enough. Now, take the letters of a second, drop the O (that's "nothing" gone), and then "somehow" tells you to anagram what's left to get your answer.