Calm as a non-runner (5)

I believe the answer is:

still

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'calm' is the definition.
(I know that calm can be written as still)

I can't explain the remainder of the clue.

(Other definitions for still that I've seen before include "Stop" , "Unmoving yet" , "Where to make spirits" , "... [STRONG LIQUOR] produced by this" , "sort of life" .)

I've seen this clue in the Evening Standard.

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