1. Without official authorization
   "he had made some money on the side"
   - unofficially

Encyclopedia: On the side

• oxidative
• oxidative phosphorylation
• oxide
• oxidisable
• oxidisation
• oxidise
• oxidised
• oxidised LDL cholesterol
• oxidiser
• oxidising agent
• oxidizable
• oxidization
• oxidize
• oxidized
• oxidized LDL cholesterol
• oxidizer
• oxidizing agent
• oxidoreductase
• oxidoreduction
• oxime
• oximeter
• oxlip
• Oxonian
• oxtail
• oxtail soup