Frighten out of Soho? (4)
I believe the answer is:
shoo
'frighten' is the definition.
(e.g. shooing birds away)
'of soho?' is the wordplay.
'of' is an anagram indicator (the answer comes from or 'of' the letters).
'soho' anagrammed gives 'SHOO'.
'out' acts as a link.
(Other definitions for shoo that I've seen before include "Begone!" , "Expression to chase away an animal" , "told to go away!" , "Scary cry" , "Buzz off!" .)