26 across
A
couple
of
hairstyles,
extremely
smart
feature
of
the
Arctic
(10)
A couple of hairstyles, extremely smart feature of the Arctic (10)
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The definition is at the end of the clue.
How the clue works
Right, so feature of the Arctic is what we're defining - that permanently frozen ground you get up north. For the wordplay, take two hairstyles, PERM and AFRO, stick them together, then tack on ST, which is just the outer letters ("extremely") of "smart" - and that builds PERMAFROST.