Shock husband with outward appearance (4)
I believe the answer is:
hair
'shock' is the definition.
(shock can mean a mass of hair)
'husband with outward appearance' is the wordplay.
'husband' becomes 'h' (abbreviation).
'with' is a charade indicator (letters next to each other).
'outward appearance' becomes 'air' (I've seen this in another clue).
'h'+'air'='HAIR'
(Other definitions for hair that I've seen before include "It grows from the skin" , "Coiffure" , "Hirsute hippy musical with song 'aquarius'" , "A very small quantity" , "Fuzz" .)