Almost entirely; nearly entirely; almost completely.
"Well-nigh" Examples
Usage Examples:
The entire town was affected by the flood, which was well-nigh unbelievable to those who had lived there all their lives. The new policy is well-nigh impossible to understand, and employees are struggling to keep up with the changes. After months of working late nights, Sarah felt well-nigh exhausted and desperately needed a break. The journey was well-nigh impossible, as the road was treacherous and the weather was catching up on us. The new restaurant is nearly complete, and it is well-nigh ready for its grand opening.