Could be five hundred on the street or a thousand, stirring things up in very dry place (9)
I believe the answer is:
sandstorm
'stirring things up in very dry place' is the definition.
I can't judge whether this definition defines the answer.
'could be five hundred on the street or a thousand' is the wordplay.
'could' becomes 'san' (I can't explain this - if you can you should believe this answer much more).
'be five hundred' becomes 'D' (Roman numeral for 500).
'on' is a charade indicator (letters next to each other).
'the street' becomes 'st' (abbreviation).
'a thousand' becomes 'M' (Roman numeral for a thousand).
'san'+'d'+'st'+'or'+'m'='SANDSTORM'
Can you help me to learn more?
(Other definitions for sandstorm that I've seen before include "Desert peril" , "Result of strong desert wind" , "that's gritty and violent" , "Desert hazard" .)