Hostile West African country gets biting insect around November (9)
I believe the answer is:
malignant
'hostile' is the definition.
(thesaurus)
'west african country gets biting insect around november' is the wordplay.
'west african country' becomes 'mali' (I've seen this before).
'gets' is a charade indicator (letters next to each other).
'biting insect' becomes 'gnat' (I've seen this before).
'around' is an insertion indicator.
'november' becomes 'n' (phonetic alphabet: alpha, bravo, charlie etc.).
'gnat' going around 'n' is 'gnant'.
'mali'+'gnant'='MALIGNANT'
(Other definitions for malignant that I've seen before include "Seeking to harm others" , "Very bad" , "Feeling or showing great ill will, cancerous" , "Spiteful" , "Not benign" .)