1. Of biological parents not married to each other
   - illegitimately 
2. Of unwed parents
   "he was born out of wedlock"
   - outside marriage

Encyclopedia: Out of wedlock

• fiat
• fiat money
• fib
• fibber
• fibbing
• fiber
• fiber bundle
• fiber optic cable
• fiber-optic transmission system
• fiberboard
• fiberglass
• fiberoptic
• fiberoptics
• fiberscope
• Fibonacci number
• Fibonacci sequence
• fibre
• fibre bundle
• fibre optic cable
• fibre-optic transmission system
• fibreboard
• fibreglass
• fibreoptic
• fibreoptics
• fibrescope