A bigwig, royal, yet not a nice type (5)
I believe the answer is:
viper
'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' (I've seen this in another clue).
'royal' becomes 'ER' (abbreviation for Elizabeth Regina).
'vip'+'er'='VIPER'
'yet' acts as a link.
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" .)