A bigwig, royal, yet not a nice type (5)
I believe the answer is:
viper
'yet not a nice type' is the definition.
I can't judge whether this definition defines the answer.
'a bigwig royal' is the wordplay.
'a bigwig' becomes 'VIP'.
'royal' becomes 'er' (abbreviation for Elizabeth Regina).
'vip'+'er'='VIPER'
Can you help me to learn more?
(Other definitions for viper that I've seen before include "Malicious type" , "spiteful person" , "A small poisonous snake" , "Deadly-venomous snake" , "Adder" .)